CN117321105A - Method for producing fluorine-containing polymer, method for producing polytetrafluoroethylene, and composition - Google Patents

Method for producing fluorine-containing polymer, method for producing polytetrafluoroethylene, and composition Download PDF

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Publication number
CN117321105A
CN117321105A CN202280035302.5A CN202280035302A CN117321105A CN 117321105 A CN117321105 A CN 117321105A CN 202280035302 A CN202280035302 A CN 202280035302A CN 117321105 A CN117321105 A CN 117321105A
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group
polymer
monomer
mass
carbon atoms
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Inventor
难波义典
玉井利奈
岩阪拓马
土屋壮司
市川贤治
加藤丈人
入江正树
山中拓
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Daikin Industries Ltd
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Daikin Industries Ltd
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Priority claimed from PCT/JP2022/020583 external-priority patent/WO2022244784A1/en
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Abstract

The present invention provides a method for producing a fluoropolymer by polymerizing a perfluoromonomer in an aqueous medium in the presence of a polymer (1), wherein the content of polymerized units based on the perfluoromonomer in the fluoropolymer is 90 mol% or more relative to the total polymerized units of the fluoropolymer, and the polymer (1) is represented by the general formula (1): CF (compact flash) 2 ＝CF‑O‑R‑(Rf‑SO 3 M) m The polymers of the monomers (1) shown, the polymerized units (1) in the polymers (1) based on the monomers (1) being relative to the polymers (1)The total polymerized units are 50% by mass or more, and the content of dimers and trimers of the monomer (1) in the polymer (1) is 1.0% by mass or less relative to the polymer (1).

Description

Method for producing fluorine-containing polymer, method for producing polytetrafluoroethylene, and composition
Technical Field
The present invention relates to a method for producing a fluoropolymer, a method for producing polytetrafluoroethylene, and a composition.
Background
Patent document 1 describes a method for producing a fluoropolymer, which comprises emulsion-polymerizing 1 or more fluorinated monomers in an aqueous medium, wherein the aqueous emulsion-polymerization is carried out in the presence of at least 1 radical initiator and at least 1 polyfunctional dispersant [ dispersant (D) ] in an aqueous medium, and wherein the dispersant (D):
Comprising a backbone chain comprising repeat units from more than 1 ethylenically unsaturated monomer,
the above-mentioned dispersant (D) has a molecular weight and its distribution such that it does not substantially contain a fraction having a molecular weight of less than 3000,
-comprises a compound selected from the group consisting of-SO 3 X a 、-PO 3 X a and-COOX a (X a Is H, an ammonium group or a monovalent metal)A mass in an amount of at least 1.75meq/g relative to the weight of the dispersant (D),
the dispersant (D) is used in an amount of 0.01% by weight and 5.00% by weight, based on the total weight of the aqueous medium.
Patent document 2 describes a method for producing a fluoropolymer, which includes the steps of: the fluorine-containing polymer is obtained by polymerizing a fluorine-containing monomer in an aqueous medium in the presence of a polymer (1) comprising a polymerization unit (1) based on a monomer represented by the following general formula (1).
CX 2 ＝CY(-CZ 2 -O-Rf-A) (1)
(wherein X is the same or different and is-H or-F, Y is-H, -F, alkyl or fluoroalkyl, Z is the same or different and is-H, -F, alkyl or fluoroalkyl, rf is a fluoroalkyl having 1 to 40 carbon atoms or a fluoroalkyl having 2 to 100 carbon atoms and having an ether bond A is-COOM, -SO) 3 M or-OSO 3 M (M is-H, a metal atom, -NR) 7 4 Imidazolium with or without substituents, pyridinium with or without substituents or phosphonium with or without substituents, R 7 Is H or an organic group. Wherein at least 1 of X, Y and Z contains a fluorine atom. )
Patent document 3 describes a method for producing an aqueous fluoropolymer dispersion, which comprises the following step a: the fluoropolymer is obtained by polymerizing in the presence of a polymer (I) comprising a polymerization unit (I) based on a monomer represented by the following general formula (I), wherein the polymer (I) is not included, and the aqueous dispersion before treatment comprising the fluoropolymer is subjected to ultrafiltration, microfiltration or dialysis membrane treatment, or a combination thereof.
CX 1 X 3 ＝CX 2 R(-CZ 1 Z 2 -A 0 ) m (I)
(wherein X is 1 And X 3 Each independently F, cl, H or CF 3 ；X 2 H, F, alkyl or fluoroalkyl; a is that 0 Is an anionic group; r is a linking group; z is Z 1 And Z 2 Each independently is H, F, alkylOr a fluoroalkyl group; m is an integer of 1 or more. )
Prior art literature
Patent literature
Patent document 1: japanese patent application laid-open No. 2020-510737
Patent document 2: international publication No. 2019/168883
Patent document 3: international publication No. 2020/218620
Disclosure of Invention
Problems to be solved by the invention
The present invention provides a method for producing a fluoropolymer using a polymer having a plurality of sulfonic acid groups or sulfonate groups, which is capable of producing a fluoropolymer containing a high content of polymerized units based on a perfluorinated monomer, substantially free of dimers and trimers of monomers constituting the polymer.
Another object of the present invention is to provide a method for producing polytetrafluoroethylene using a polymer having a sulfonic acid group or a sulfonate group, which is capable of producing polytetrafluoroethylene having a high molecular weight substantially free of dimers and trimers of monomers constituting the polymer.
Further, an object of the present invention is to provide a composition containing a polymer having a plurality of sulfonic acid groups or sulfonate groups and a fluoropolymer containing a polymerized unit based on a perfluorinated monomer in a high content, and substantially free of dimers and trimers of monomers constituting the polymer.
The present invention also provides a composition containing a polymer having a sulfonic acid group or a sulfonate group and polytetrafluoroethylene having a high molecular weight, and substantially free of dimers and trimers of monomers constituting the polymer.
Means for solving the problems
According to the present invention, there is provided a method for producing a fluorine-containing polymer by polymerizing a perfluoromonomer in an aqueous medium in the presence of a polymer (1), wherein the content of polymerized units based on the perfluoromonomer in the fluorine-containing polymer is 90 mol% or more with respect to the total polymerized units of the fluorine-containing polymer, the polymer (1) is a polymer of a monomer (1) represented by the general formula (1), the polymerized units (1) based on the monomer (1) in the polymer (1) are 50 mass% or more with respect to the total polymerized units of the polymer (1), and the content of dimers and trimers of the monomer (1) in the polymer (1) is 1.0 mass% or less with respect to the polymer (1).
CF 2 ＝CF-O-R-(Rf-SO 3 M) m (1)
(wherein R is a single bond or a linking group; rf is a fluorine-containing alkylene group having 1 to 40 carbon atoms or a fluorine-containing alkylene group having 2 to 100 carbon atoms and having an ether bond or a ketone group; M is H, a metal atom, NR) 7 4 An imidazolium with or without substituents, a pyridinium with or without substituents, or a phosphonium with or without substituents; r is R 7 Is H or an organic group; m is an integer of 1 or more. )
In the production method of the present invention, the monomer (1) is preferably the monomer (2) represented by the general formula (2).
CF 2 ＝CF-O-Rf-SO 3 M (2)
(wherein Rf and M are as described above.)
In the production method of the present invention, the fluoropolymer is preferably polytetrafluoroethylene.
In the production method of the present invention, the fluoropolymer is preferably a perfluoroelastomer.
Further, according to the present invention, there is provided a method for producing polytetrafluoroethylene by polymerizing tetrafluoroethylene in an aqueous medium in the presence of a polymer (1), wherein the polytetrafluoroethylene is a high molecular weight polytetrafluoroethylene, the polymer (1) is a polymer of a monomer (1) represented by the general formula (1), and the content of dimers and trimers of the monomer (1) in the polymer (1) is 1.0 mass% or less relative to the polymer (1).
CF 2 ＝CF-O-R-(Rf-SO 3 M) m (1)
(wherein R is a single bond or a linking group; rf is a fluorine-containing subunit having 1 to 40 carbon atomsAn alkyl group or a fluorinated alkylene group having an ether bond or a ketone group and having 2 to 100 carbon atoms; m is H, a metal atom, NR 7 4 An imidazolium with or without substituents, a pyridinium with or without substituents, or a phosphonium with or without substituents; r is R 7 Is H or an organic group; m is an integer of 1 or more. )
In the production method of the present invention, the monomer (1) is preferably the monomer (2) represented by the general formula (2).
CF 2 ＝CF-O-Rf-SO 3 M (2)
(wherein Rf and M are as described above.)
Further, according to the present invention, there is provided a composition comprising a polymer (1) and a fluorine-containing polymer, wherein the fluorine-containing polymer contains polymerized units based on a perfluorinated monomer, the content of polymerized units based on the perfluorinated monomer in the fluorine-containing polymer is 90 mol% or more relative to the total polymerized units of the fluorine-containing polymer, the polymer (1) is a polymer of a monomer (1) represented by the general formula (1), the polymerized units (1) based on the monomer (1) in the polymer (1) are 50 mass% or more relative to the total polymerized units of the polymer (1), and the content of dimers and trimers of the monomer (1) in the polymer (1) is 1.0 mass% or less relative to the polymer (1).
CF 2 ＝CF-O-R-(Rf-SO 3 M) m (1)
(wherein R is a single bond or a linking group; rf is a fluorine-containing alkylene group having 1 to 40 carbon atoms or a fluorine-containing alkylene group having 2 to 100 carbon atoms and having an ether bond or a ketone group; M is H, a metal atom, NR) 7 4 An imidazolium with or without substituents, a pyridinium with or without substituents, or a phosphonium with or without substituents; r is R 7 Is H or an organic group; m is an integer of 1 or more. )
In the composition of the present invention, the monomer (1) is preferably the monomer (2) represented by the general formula (2).
CF 2 ＝CF-O-Rf-SO 3 M (2)
(wherein Rf and M are as described above.)
The invention is characterized in thatIn the composition, the polymer (1) is preferably a monomer (1) and a polymer of the formula CFR 11 ＝CR 11 2 (wherein R is 11 H, F or a perfluoroalkyl group having 1 to 4 carbon atoms).
In the composition of the present invention, it is preferable that the content of the polymerized unit (1) based on the monomer (1) is 50 to 94% by mass based on the total polymerized units constituting the polymer (1), based on the general formula CFR 11 ＝CR 11 2 (wherein R is 11 The content of the polymerized units (M) of the monomer represented by H, F or a perfluoroalkyl group having 1 to 4 carbon atoms independently is preferably 6 to 50% by mass relative to the total polymerized units constituting the polymer (1).
In the composition of the present invention, the alternation ratio of the polymerized units (1) and the polymerized units (M) is preferably 40% or more.
In the composition of the present invention, the fluoropolymer is preferably polytetrafluoroethylene.
In the composition of the present invention, the fluoropolymer is preferably a perfluoroelastomer.
In the composition of the present invention, when the fluoropolymer is the polytetrafluoroethylene or the perfluoroelastomer, the metal content in the composition is preferably 10 mass ppm or less.
Further, according to the present invention, there is provided a composition comprising a polymer (1) and polytetrafluoroethylene, wherein the polytetrafluoroethylene is a high molecular weight polytetrafluoroethylene, the polymer (1) is a polymer of a monomer (1) represented by the general formula (1), and the content of a dimer and a trimer of the monomer (1) in the polymer (1) is 1.0 mass% or less with respect to the polymer (1).
CF 2 ＝CF-O-R-(Rf-SO 3 M) m (1)
(wherein R is a single bond or a linking group; rf is a fluorine-containing alkylene group having 1 to 40 carbon atoms or a fluorine-containing alkylene group having 2 to 100 carbon atoms and having an ether bond or a ketone group; M is H, a metal atom, NR) 7 4 Imidazolium with or without substituents, pyridinium with or without substituents or phosphorus with or without substituentsAn onium; r is R 7 Is H or an organic group; m is an integer of 1 or more. )
In the composition of the present invention, the monomer (1) is preferably the monomer (2) represented by the general formula (2).
CF 2 ＝CF-O-Rf-SO 3 M (2)
(wherein Rf and M are as described above.)
ADVANTAGEOUS EFFECTS OF INVENTION
According to the present invention, it is possible to provide a production method for producing a fluorine-containing polymer using a polymer having a plurality of sulfonic acid groups or sulfonate groups, which is capable of producing a fluorine-containing polymer containing a polymerized unit based on a perfluorinated monomer in a high content, substantially free of dimers and trimers of monomers constituting the polymer.
Further, according to the present invention, it is an object to provide a method for producing polytetrafluoroethylene using a polymer having a sulfonic acid group or a sulfonate group, which is capable of producing polytetrafluoroethylene having a high molecular weight substantially free of dimers and trimers of monomers constituting the polymer.
Further, according to the present invention, there can be provided a composition containing a polymer having a plurality of sulfonic acid groups or sulfonate groups and a fluoropolymer containing a polymerized unit based on a perfluorinated monomer in a high content, and substantially free of dimers and trimers of monomers constituting the polymer.
Further, according to the present invention, there can be provided a composition containing a polymer having a sulfonic acid group or a sulfonate group and polytetrafluoroethylene having a high molecular weight, and substantially free of dimers and trimers of monomers constituting the polymer.
Detailed Description
Before explaining the present invention in detail, some terms used in the present invention are defined or explained.
In the present invention, the fluororesin means a partially crystalline fluoropolymer and is a fluoroplastic. The fluororesin has a melting point, has a thermoplastic property, and may be melt-processable or non-melt-processable.
In the present invention, melt processability means that a polymer can be melted and processed by conventional processing equipment such as an extruder and an injection molding machine. Therefore, the melt-processible fluororesin generally has a melt flow rate of 0.01g/10 min to 500g/10 min as measured by a measurement method described later.
In the present invention, the fluororubber means an amorphous fluoropolymer. The "amorphous state" means that the melting peak (. DELTA.H) appearing in the differential scanning calorimeter [ DSC ] (temperature rise: 10 ℃/min) or the differential thermal analysis [ DTA ] (temperature rise: 10 ℃/min) of the fluorine-containing polymer is 4.5J/g or less. The fluororubber exhibits elastomeric properties by undergoing crosslinking. The elastomeric properties refer to the following properties: the polymer can be stretched and can retain its original length when the force required for stretching the polymer has not been applied.
In the present invention, the partially fluorinated rubber is a fluoropolymer having a content of a fluorinated monomer unit or a perfluorinated monomer unit of less than 90 mol% based on the total polymerized units, and having a glass transition temperature of 20 ℃ or lower and a melting peak (Δh) size of 4.5J/g or lower.
In the present invention, the perfluororubber (perfluoroelastomer) is a fluoropolymer having a content of perfluoromonomer units of 90 mol% or more, preferably 91 mol% or more, based on all the polymerized units, and has a glass transition temperature of 20 ℃ or less and a melting peak (Δh) size of 4.5J/g or less, and further has a concentration of fluorine atoms contained in the fluoropolymer of 71 mass% or more, preferably 71.5 mass% or more. In the present invention, the concentration (mass%) of fluorine atoms contained in the fluoropolymer is calculated from the types and contents of the respective monomers constituting the fluoropolymer, with respect to the concentration of fluorine atoms contained in the fluoropolymer.
In the present invention, a perfluoromonomer refers to a monomer that does not contain a carbon atom-hydrogen atom bond in the molecule. The perfluorinated monomer may be a monomer having a plurality of fluorine atoms bonded to carbon atoms in addition to carbon atoms and fluorine atoms, substituted with chlorine atoms, or may be a monomer having a nitrogen atom, an oxygen atom, a sulfur atom, a phosphorus atom, a boron atom or a silicon atom in addition to carbon atoms. As the above-mentioned perfluorinated monomer, a monomer in which all hydrogen atoms are replaced with fluorine atoms is preferable. The perfluorinated monomer does not include a monomer that provides a crosslinking site.
The monomer providing a crosslinking site means a monomer having a crosslinkable group (vulcanization point monomer) which provides a crosslinking site for forming a crosslink by a curing agent to the fluoropolymer.
In the present invention, polytetrafluoroethylene [ PTFE ] is preferably a fluoropolymer having a tetrafluoroethylene unit content of 99 mol% or more based on the total polymerized units.
In the present invention, the fluororesin (excluding polytetrafluoroethylene) and the fluororubber are both preferably a fluoropolymer having a tetrafluoroethylene content of less than 99 mol% relative to the total polymerized units.
In the present invention, the content of each monomer constituting the fluoropolymer can be calculated by appropriately combining NMR, FT-IR, elemental analysis, and fluorescent X-ray analysis according to the kind of monomer.
In the present invention, the term "organic group" refers to a group containing 1 or more carbon atoms or a group formed by removing 1 hydrogen atom from an organic compound.
Examples of such "organic groups" include:
an alkyl group which may have 1 or more substituents,
Alkenyl group which may have 1 or more substituents,
Alkynyl group which may have 1 or more substituent(s),
Cycloalkyl group which may have 1 or more substituents,
Cycloalkenyl group which may have 1 or more substituent(s),
A cycloalkadienyl group which may have 1 or more substituents,
Aryl group which may have 1 or more substituents,
Aralkyl group which may have 1 or more substituent(s),
A non-aromatic heterocyclic group which may have 1 or more substituents,
Heteroaryl group which may have 1 or more substituents,
Cyano group,
Formyl group,
RaO-、
RaCO-、
RaSO 2 -、
RaCOO-、
RaNRaCO-、
RaCONRa-、
RaOCO-、
RaOSO 2 -, a
RaNRbSO 2 -
(wherein Ra is independently
An alkyl group which may have 1 or more substituents,
Alkenyl group which may have 1 or more substituents,
Alkynyl group which may have 1 or more substituent(s),
Cycloalkyl group which may have 1 or more substituents,
Cycloalkenyl group which may have 1 or more substituent(s),
A cycloalkadienyl group which may have 1 or more substituents,
Aryl group which may have 1 or more substituents,
Aralkyl group which may have 1 or more substituent, non-aromatic heterocyclic group which may have 1 or more substituent, or
Heteroaryl groups which may have 1 or more substituents,
rb is independently H or an alkyl group which may have 1 or more substituents).
The organic group is preferably an alkyl group which may have 1 or more substituents.
In the present invention, the term "substituent" means a group which can be substituted. Examples of such "substituents" include: aliphatic group, aromatic group, heterocyclic group, acyl group, acyloxy group, acylamino group, aliphatic oxy group, aromatic oxy group, heterocyclic oxy group, aliphatic oxycarbonyl group, aromatic oxycarbonyl group, heterocyclic oxycarbonyl group, carbamoyl group, aliphatic sulfonyl group, aromatic sulfonyl group, heterocyclic sulfonyl group, aliphatic sulfonyloxy group, aromatic sulfonyloxy group, heterocyclic sulfonyloxy group, sulfamoyl group, aliphatic sulfonylamino group, aromatic sulfonylamino group, heterocyclic sulfonylamino group, amino group, aliphatic amino group, aromatic amino group, heterocyclic amino group, aliphatic oxycarbonylamino group, aromatic oxycarbonylamino group, heterocyclic oxycarbonylamino group, aliphatic sulfinyl group, aromatic sulfinyl group, aliphatic thio group, aromatic thio group, hydroxyl group, cyano group, sulfo group, carboxyl group, aliphatic sulfonylamino group, aromatic sulfonylamino group, sulfamoylamino group, halogen atom, sulfamoylcarbamoyl group, carbamoyl sulfamoyl group, dialiphatic oxygen phosphino group and aromatic phosphino group.
The aliphatic group may be saturated or unsaturated, and may have a hydroxyl group, an aliphatic oxy group, a carbamoyl group, an aliphatic oxycarbonyl group, an aliphatic thio group, an amino group, an aliphatic amino group, an amido group, a carbamoyl amino group, or the like. Examples of the aliphatic group include an alkyl group having 1 to 8 carbon atoms, preferably 1 to 4 carbon atoms, such as a methyl group, an ethyl group, a vinyl group, a cyclohexyl group, and a carbamoylmethyl group.
The aromatic group may have, for example, a nitro group, a halogen atom, an aliphatic oxy group, a carbamoyl group, an aliphatic oxycarbonyl group, an aliphatic thio group, an amino group, an aliphatic amino group, an amido group, a carbamoyl amino group, or the like. Examples of the aromatic group include an aryl group having 6 to 12 carbon atoms, preferably 6 to 10 total carbon atoms, for example, phenyl group, 4-nitrophenyl group, 4-acetylaminophenyl group, 4-methanesulfonylphenyl group, and the like.
The heterocyclic group may have a halogen atom, a hydroxyl group, an aliphatic oxy group, a carbamoyl group, an aliphatic oxycarbonyl group, an aliphatic thio group, an amino group, an aliphatic amino group, an amido group, a carbamoyl amino group, or the like. Examples of the heterocyclic group include a 5-to 6-membered heterocyclic group having 2 to 12 carbon atoms, preferably 2 to 10 carbon atoms, for example, a 2-tetrahydrofuranyl group and a 2-pyrimidinyl group.
The acyl group may have an aliphatic carbonyl group, an arylcarbonyl group, a heterocyclic carbonyl group, a hydroxyl group, a halogen atom, an aromatic group, an aliphatic oxy group, a carbamoyl group, an aliphatic oxycarbonyl group, an aliphatic thio group, an amino group, an aliphatic amino group, an amido group, a carbamoyl amino group, or the like. Examples of the acyl group include an acyl group having 2 to 8 carbon atoms, preferably 2 to 4 carbon atoms, for example, an acetyl group, a propionyl group, a benzoyl group, a 3-pyridinecarbonyl group, and the like.
The amido group may have an aliphatic group, an aromatic group, a heterocyclic group, or the like, and may have an acetylamino group, a benzoylamino group, a 2-pyridylcarbonylamino group, a propionylamino group, or the like, for example. Examples of the amido group include an amido group having 2 to 12 carbon atoms in total, preferably 2 to 8 carbon atoms, an alkylcarbonylamino group having 2 to 8 carbon atoms in total, for example, an acetylamino group, a benzoylamino group, a 2-pyridinecarbonylamino group, and a propionylamino group.
The aliphatic oxycarbonyl group may be saturated or unsaturated, and may have a hydroxyl group, an aliphatic oxy group, a carbamoyl group, an aliphatic oxycarbonyl group, an aliphatic thio group, an amino group, an aliphatic amino group, an amido group, a carbamoyl amino group, or the like. Examples of the aliphatic oxycarbonyl group include an alkoxycarbonyl group having 2 to 8 carbon atoms, preferably 2 to 4 carbon atoms, for example, a methoxycarbonyl group, an ethoxycarbonyl group, a t-butoxycarbonyl group, and the like.
The carbamoyl group may have an aliphatic group, an aromatic group, a heterocyclic group, or the like. Examples of the carbamoyl group include an unsubstituted carbamoyl group, an alkylcarbamoyl group having 2 to 9 total carbon atoms, preferably an unsubstituted carbamoyl group, an alkylcarbamoyl group having 2 to 5 total carbon atoms, for example, an N-methylcarbamoyl group, an N, N-dimethylcarbamoyl group, an N-phenylcarbamoyl group and the like.
The aliphatic sulfonyl group may be saturated or unsaturated, and may have a hydroxyl group, an aromatic group, an aliphatic oxy group, a carbamoyl group, an aliphatic oxycarbonyl group, an aliphatic thio group, an amino group, an aliphatic amino group, an amido group, a carbamoyl amino group, or the like. Examples of the aliphatic sulfonyl group include alkylsulfonyl groups having 1 to 6 total carbon atoms, preferably 1 to 4 total carbon atoms, such as methanesulfonyl.
The aromatic sulfonyl group may have a hydroxyl group, an aliphatic oxy group, a carbamoyl group, an aliphatic oxycarbonyl group, an aliphatic thio group, an amino group, an aliphatic amino group, an amido group, a carbamoyl amino group, or the like. Examples of the aromatic sulfonyl group include arylsulfonyl groups having 6 to 10 total carbon atoms, for example, benzenesulfonyl groups.
The amino group may have an aliphatic group, an aromatic group, a heterocyclic group, or the like.
The above-mentioned acylamino group may have, for example, an acetylamino group, a benzoylamino group, a 2-pyridinecarbonylamino group, a propionylamino group, or the like. Examples of the amido group include an amido group having 2 to 12 total carbon atoms, preferably 2 to 8 total carbon atoms, and more preferably an alkylcarbonylamino group having 2 to 8 total carbon atoms, for example, an acetylamino group, a benzoylamino group, a 2-pyridinecarbonylamino group, a propionylamino group, and the like.
The aliphatic sulfonamide group, aromatic sulfonamide group, heterocyclic sulfonamide group may be, for example, methanesulfonamide group, benzenesulfonamide group, 2-pyridinesulfonamide group, or the like.
The sulfamoyl group may have an aliphatic group, an aromatic group, a heterocyclic group, or the like. Examples of the sulfamoyl group include a sulfamoyl group, an alkylsulfamoyl group having 1 to 9 total carbon atoms, a dialkylsulfamoyl group having 2 to 10 total carbon atoms, an arylsulfamoyl group having 7 to 13 total carbon atoms, a heterocyclic sulfamoyl group having 2 to 12 total carbon atoms, more preferably a sulfamoyl group, an alkylsulfamoyl group having 1 to 7 total carbon atoms, a dialkylsulfamoyl group having 3 to 6 total carbon atoms, an arylsulfamoyl group having 6 to 11 total carbon atoms, a heterocyclic sulfamoyl group having 2 to 10 total carbon atoms, such as a sulfamoyl group, a methylsulfamoyl group, an N, N-dimethylsulfamoyl group, a phenylsulfamoyl group, and a 4-pyridinesulfamoyl group.
The aliphatic oxy group may be saturated or unsaturated, and may have methoxy, ethoxy, isopropoxy, cyclohexyloxy, methoxyethoxy, or the like. Examples of the aliphatic oxy group include an alkoxy group having 1 to 8 carbon atoms, preferably 1 to 6 carbon atoms, such as methoxy, ethoxy, isopropoxy, cyclohexyloxy, methoxyethoxy, and the like.
The aromatic amino group and the heterocyclic amino group may have an aliphatic group, an aliphatic oxy group, a halogen atom, a carbamoyl group, a heterocyclic group condensed with the aryl group, or an aliphatic oxycarbonyl group, and preferably may have an aliphatic group having 1 to 4 total carbon atoms, an aliphatic oxy group having 1 to 4 total carbon atoms, a halogen atom, a carbamoyl group having 1 to 4 total carbon atoms, a nitro group, or an aliphatic oxycarbonyl group having 2 to 4 total carbon atoms.
The aliphatic thio group may be saturated or unsaturated, and examples thereof include alkylthio groups having 1 to 8 total carbon atoms, more preferably 1 to 6 total carbon atoms, such as methylthio, ethylthio, carbamoyl methylthio, t-butylthio and the like.
The carbamoylamino group may have an aliphatic group, an aryl group, a heterocyclic group, or the like. Examples of the carbamoylamino group include carbamoylamino group, alkylcarbamoylamino group having 2 to 9 total carbon atoms, dialkylcarbamoylamino group having 3 to 10 total carbon atoms, arylcarbamoylamino group having 7 to 13 total carbon atoms, heterocyclylcarbamoylamino group having 3 to 12 total carbon atoms, preferably carbamoylamino group, alkylcarbamoylamino group having 2 to 7 total carbon atoms, dialkylcarbamoylamino group having 3 to 6 total carbon atoms, arylcarbamoylamino group having 7 to 11 total carbon atoms, heterocyclylcarbamoylamino group having 3 to 10 total carbon atoms, for example, carbamoylamino group, methylcarbamoylamino group, N-dimethylcarbamoylamino group, phenylcarbamoylamino group, 4-pyridinecarbamoylamino group and the like.
In the present invention, all values included in the range (for example, 1.4, 1.9, 2.33, 5.75, 9.98, etc. are included in 1 to 10) are included in the range indicated by the end points.
In the present invention, the expression "at least 1" includes all values of 1 or more (for example, at least 2, at least 4, at least 6, at least 8, at least 10, at least 25, at least 50, at least 100, etc.).
Hereinafter, specific embodiments of the present invention will be described in detail, but the present invention is not limited to the following embodiments.
The production method of the present invention is a method for producing a fluoropolymer by polymerizing a perfluoromonomer in an aqueous medium in the presence of the polymer (1) (hereinafter, sometimes referred to as the 1 st production method of the present invention).
< Polymer (1) >
The polymer (1) used in the production method 1 of the present invention is a polymer of a monomer (1) represented by the general formula (1), wherein the amount of polymerized units (1) based on the monomer (1) in the polymer (1) is 50 mass% or more relative to the total polymerized units of the polymer (1), and the amount of dimers and trimers of the monomer (1) in the polymer (1) is 1.0 mass% or less relative to the polymer (1).
The monomer (1) is represented by the following general formula (1).
CF 2 ＝CF-O-R-(Rf-SO 3 M) m (1)
(wherein R is a single bond or a linking group; rf is a fluorine-containing alkylene group having 1 to 40 carbon atoms or a fluorine-containing alkylene group having 2 to 100 carbon atoms and having an ether bond or a ketone group; M is H, a metal atom, NR) 7 4 An imidazolium with or without substituents, a pyridinium with or without substituents, or a phosphonium with or without substituents; r is R 7 Is H or an organic group; m is an integer of 1 or more. )
In the production method of the present invention, 1 or 2 or more monomers can be used as the monomer (1).
The polymer (1) may be a homopolymer of the monomer (1) or a copolymer with other monomers.
R is a single bond or a linking group. In the present invention, the "linking group" is a (m+1) -valent linking group, and in the case where m is 1, it is a divalent linking group. The linking group preferably contains at least 1 carbon atom, and the number of carbon atoms may be 2 or more, 4 or more, 8 or more, 10 or more, or 20 or more. The upper limit is not limited, and may be, for example, 100 or less, or 50 or less.
The linking group may be a chain or branched, cyclic or acyclic structure, saturated or unsaturated, substituted or unsubstituted, may contain 1 or more heteroatoms selected from the group consisting of sulfur, oxygen and nitrogen as desired, and may contain 1 or more functional groups selected from the group consisting of esters, amides, sulfonamides, carbonyl groups, carbonates, carbamates, ureas and carbamates as desired. The linking group contains no carbon atom and may be a chain hetero atom such as oxygen, sulfur or nitrogen.
m is an integer of 1 or more, preferably 1 or 2, more preferably 1. When M is an integer of 2 or more, rf and M may be the same or different.
Next, a preferred configuration in the case where m is 1 in the general formula (1) will be described.
In the case where m is 1 in the general formula (1), R is preferably a single bond.
That is, the monomer (1) is preferably the monomer (2) represented by the general formula (2).
The polymer (1) is also preferably a polymer (2) comprising polymerized units (2) based on a monomer (2) represented by the general formula (2).
CF 2 ＝CF-O-Rf-SO 3 M (2)
(wherein Rf and M are as described above.)
The Rf is a fluorine-containing alkylene group having 1 to 40 carbon atoms, a fluorine-containing alkylene group having 2 to 100 carbon atoms and having an ether bond, or a fluorine-containing alkylene group having 2 to 100 carbon atoms and having a ketone group. The above-mentioned fluorinated alkylene group having an ether bond having 2 to 100 carbon atoms is an alkylene group having an ether bond between carbon atoms and having a structure not including an oxygen atom as a terminal.
The number of carbon atoms of the fluorine-containing alkylene group of Rf is preferably 2 or more. The number of carbon atoms of the fluorinated alkylene group is preferably 30 or less, more preferably 20 or less, further preferably 10 or less, particularly preferably 5 or less. As the fluorine-containing alkylene group, there may be mentioned-CF 2 -、-CH 2 CF 2 -、-CF 2 CF 2 -、-CF 2 CH 2 -、-CF 2 CF 2 CH 2 -、-CF(CF 3 )-、-CF(CF 3 )CF 2 -、-CF(CF 3 )CH 2 -、-CF 2 CF 2 CF 2 -、-CF 2 CF 2 CF 2 CF 2 -and the like. The fluorinated alkylene group is preferably a perfluoroalkylene group, and more preferably an unbranched linear perfluoroalkylene group.
The number of carbon atoms of the above-mentioned fluorine-containing alkylene group having an ether bond is preferably 3 or more. The number of carbon atoms of the above-mentioned fluorinated alkylene group having an ether bond is preferably 60 or less, more preferably 30 or less, further preferably 12 or less, particularly preferably 5 or less. The above-mentioned fluorinated alkylene group having an ether bond is also preferably represented by the general formula:
[ chemical 1]
(wherein Z is 1 Is F or CF 3 ；Z 2 And Z 3 H or F respectively; z is Z 4 H, F or CF 3 The method comprises the steps of carrying out a first treatment on the surface of the p1+q1+r1 is an integer of 1 to 10; s1 is 0 or 1; t1 is an integer of 0 to 5).
As the above-mentioned fluorine-containing alkylene group having an ether bond, specifically, there can be mentioned-CF 2 CF(CF 3 )OCF 2 -、-CF 2 CF(CF 3 )OCF 2 CF 2 -、-CF 2 CF(CF 3 )OCF 2 CF 2 CF 2 -、-CF(CF 3 )CF 2 -O-CF(CF 3 )-、-(CF(CF 3 )CF 2 -O) n -CF(CF 3 ) - (wherein n is an integer of 1 to 10), -CF (CF) 3 )CF 2 -O-CF(CF 3 )CH 2 -、-(CF(CF 3 )CF 2 -O) n -CF(CF 3 )CH 2 - (wherein n is an integer of 1 to 10), -CH 2 CF 2 CF 2 O-CH 2 CF 2 CH 2 -、-CF 2 CF 2 CF 2 O-CF 2 -、-CF 2 CF 2 CF 2 O-CF 2 CF 2 -、-CF 2 CF 2 CF 2 O-CF 2 CF 2 CF 2 -、-CF 2 CF 2 CF 2 O-CF 2 CF 2 CH 2 -、-CF 2 CF 2 O-CF 2 -、-CF 2 CF 2 O-CF 2 CH 2 -and the like. The above-mentioned fluorinated alkylene group having an ether bond is preferably a perfluoroalkylene group.
The number of carbon atoms of the above-mentioned fluorinated alkylene group having a ketone group is preferably 3 or more. The number of carbon atoms of the above-mentioned fluorinated alkylene group having a ketone group is preferably 60 or less, more preferably 30 or less, further preferably 12 or less, particularly preferably 5 or less.
As the above-mentioned fluorinated alkylene group having a ketone group, specifically, there may be mentioned-CF 2 CF(CF 3 )CO-CF 2 -、-CF 2 CF(CF 3 )CO-CF 2 CF 2 -、-CF 2 CF(CF 3 )CO-CF 2 CF 2 CF 2 -、-CF 2 CF(CF 3 )CO-CF 2 CF 2 CF 2 CF 2 -and the like. The above-mentioned fluorinated alkylene group having a ketone group is preferably a perfluoroalkylene group.
Water may be added to the ketone group in the fluorinated alkylene group. Thus, the monomer (1) may be a hydrate. As the fluorine-containing alkylene group having water added to the ketone group, there may be mentioned-CF 2 CF(CF 3 )C(OH) 2 -CF 2 -、-CF 2 CF(CF 3 )C(OH) 2 -CF 2 CF 2 -、-CF 2 CF(CF 3 )C(OH) 2 -CF 2 CF 2 CF 2 -、-CF 2 CF(CF 3 )C(OH) 2 -CF 2 CF 2 CF 2 CF 2 -and the like.
M, which may be identical or different at each occurrence, is H, a metal atom, NR 7 4 Imidazolium with or without substituents, pyridinium with or without substituents or phosphonium with or without substituents, R 7 Is H or an organic group.
As R 7 Preferably H or C 1-10 More preferably H or C 1-4 Further preferably H or C 1-4 Is an alkane of (2)A base.
Examples of the metal atom include alkali metal (group 1) and alkaline earth metal (group 2), and Na, K, and Li are preferable.
As M, which may be identical or different at each occurrence, H, a metal atom or NR are preferred 7 4 More preferably H, alkali metal (group 1), alkaline earth metal (group 2) or NR 7 4 Further preferably H, na, K, li or NH 4 Further more preferably H, na, K or NH 4 Particularly preferably H, na or NH 4 。
The monomer represented by the general formula (1) is preferably at least 1 selected from the group consisting of monomers represented by the general formulae (1 a), (1 b), (1 c), (1 d) and (1 e).
CF 2 ＝CF-O-(CF 2 ) n1 -SO 3 M (1a)
(wherein n1 represents an integer of 1 to 10, and M is as defined above.)
CF 2 ＝CF-O-(CF 2 C(CF 3 )F) n2 -SO 3 M (1b)
(wherein n2 represents an integer of 1 to 5, and M is as defined above.)
CF 2 ＝CF-O-(CFX 1 ) n3 -SO 3 M (1c)
(wherein X is 1 Represents F or CF 3 N3 represents an integer of 1 to 10, and M is as defined above. )
CF 2 ＝CF-O-(CF 2 CFX 1 O) n4 -(CF 2 ) n6 -SO 3 M (1d)
(wherein n4 represents an integer of 1 to 10, n6 represents an integer of 1 to 3, M and X 1 The same definition as above. )
CF 2 ＝CF-O-(CF 2 CF 2 CFX 1 O) n5 -CF 2 CF 2 CF 2 -SO 3 M (1e)
(wherein n5 represents an integer of 0 to 10, M and X 1 The same definition as above. )
In the general formula (1 a), n1 is preferably an integer of 5 or less, more preferably an integer of 2 or less. Upper partM is preferably H, na, K or NH 4 。
Examples of the monomer represented by the general formula (1 a) include CF 2 ＝CF(OCF 2 CF 2 SO 3 M)、CF 2 ＝CF(OCF 2 SO 3 M)、CF 2 ＝CF(OCF 2 CF 2 CF 2 SO 3 M)、CF 2 ＝CFO(CF 2 CF 2 CF 2 CF 2 )SO 3 M (wherein M is as defined above).
In the general formula (1 b), n2 is preferably an integer of 3 or less from the viewpoint of dispersion stability of the obtained composition. The M is preferably H, na, K or NH 4 。
In the general formula (1 c), n3 is preferably an integer of 5 or less from the viewpoint of water solubility, and M is preferably H, na, K or NH 4 。
In the general formula (1 d), X is from the aspect of dispersion stability of the composition 1 preferably-CF 3 From the viewpoint of water solubility, n4 is preferably an integer of 5 or less, and M is preferably H, na, K or NH 4 。
Examples of the monomer represented by the general formula (1 d) include CF 2 ＝CFOCF 2 CF(CF 3 )OCF 2 SO 3 M、CF 2 ＝CFOCF 2 CF(CF 3 )OCF 2 CF 2 SO 3 M、CF 2 ＝CFOCF 2 CF(CF 3 )OCF 2 CF 2 CF 2 SO 3 M (wherein M is as defined above).
In the general formula (1 e), n5 is preferably an integer of 5 or less from the viewpoint of water solubility, and M is preferably H, na, K or NH 4 。
Examples of the monomer represented by the general formula (1 e) include CF 2 ＝CFOCF 2 CF 2 CF 2 SO 3 M (where M represents H, NH) 4 Or an alkali metal).
As monomer (1), CF is preferred 2 ＝CF(OCF 2 CF 2 SO 3 M) (where M is as defined above).
Next, a preferred configuration in the case where m in the general formula (1) is an integer of 2 or more will be described.
In the case where m is 2 in the general formula (1), R is preferably a linking group containing at least 1 carbon atom.
The monomer (1) is also preferably a monomer (3) represented by the general formula (3).
The polymer (1) is also preferably a polymer (3) comprising polymerized units (3) based on the monomer (3) represented by the general formula (3).
CF 2 ＝CF-O-Q F1 -CF(-Rf-SO 3 M) 2 (3)
(wherein Rf and M are as defined above, Q F A fluorine-containing alkylene group which may contain an ether bond between carbon atoms or a fluorine-containing oxyalkylene group which may contain an ether bond between carbon atoms. )
The monomer (3) represented by the general formula (3) may be
[ chemical 2]
The polymer (1) may be a homopolymer composed of only the polymerized units (1), or may be a copolymer containing the polymerized units (1) and polymerized units based on other monomers copolymerizable with the monomer represented by the general formula (1). From the viewpoint of solubility in an aqueous medium, a homopolymer composed only of the polymerized units (1) is preferable. The polymerized units (1) may be the same or different at each occurrence, and the polymer (1) may contain polymerized units (1) based on 2 or more different monomers represented by the general formula (1).
Examples of the other monomer copolymerizable with the monomer (1) include monomers represented by the following general formula.
A general formula: CX (CX) 2 ＝CX-O-Rf-COOM
(wherein X is independently F or CF 3 Rf and M are as defined in formula (1). )
As the other monomer, a general formula CFR is also preferable 11 ＝CR 11 2 (wherein R is 11 Independently H, F or C1-4 perfluoroAlkyl) monomers. In addition, as the other monomer, a fluorine-containing ethylenic monomer having 2 or 3 carbon atoms is preferable. Examples of the other monomer include CF 2 ＝CF 2 、CF 2 ＝CFCl、CH 2 ＝CF 2 、CFH＝CH 2 、CFH＝CF 2 、CF 2 ＝CFCF 3 、CH 2 ＝CFCF 3 、CH 2 ＝CHCF 3 、CHF＝CHCF 3 (E-body), chf=chcf 3 (Z body), and the like.
Among these other monomers, from the viewpoint of good copolymerization properties, the other monomers are preferably selected from the group consisting of tetrafluoroethylene (CF 2 ＝CF 2 ) Chlorotrifluoroethylene (CF) 2 =cfcl) and vinylidene fluoride (CH 2 ＝CF 2 ) At least 1 selected from the group consisting of tetrafluoroethylene and vinylidene fluoride, more preferably at least 1 selected from the group consisting of tetrafluoroethylene and vinylidene fluoride, still more preferably vinylidene fluoride. Therefore, the polymerization unit based on the above-mentioned other monomer is preferably at least 1 selected from the group consisting of a tetrafluoroethylene-based polymerization unit and a vinylidene fluoride-based polymerization unit, and further preferably a vinylidene fluoride-based polymerization unit. The polymerized units based on the other monomers described above may be the same or different at each occurrence and the fluoropolymer may contain polymerized units based on 2 or more different other monomers.
When the polymer (1) contains the polymerized unit (1) and polymerized units based on other monomers copolymerizable with the monomer (1), the content of the polymerized unit (1) based on the monomer (1) is preferably 50 to 94% by mass, more preferably 63 to 90% by mass, still more preferably 67 to 87% by mass, and the content of the polymerized unit based on the other monomers is preferably 6 to 50% by mass, more preferably 10 to 37% by mass, still more preferably 13 to 33% by mass, relative to the total polymerized units constituting the polymer (1). This constitution is based on the general formula CFR in the polymerization unit based on the other monomer copolymerizable with the monomer (1) 11 ＝CR 11 2 The polymerization unit (M) of the monomers shown is particularly preferred. The fluoropolymer contains polymerized units (1)In the case of the polymerized units (M), the total content of the polymerized units (1) and the polymerized units (M) is preferably 80 to 100 mass%, more preferably 85 mass% or more, still more preferably 90 mass% or more, particularly preferably 99 mass% or more, with respect to the total polymerized units constituting the fluoropolymer. In addition, the fluoropolymer contains polymerized units (1) and is CX-based 2 In the case of the polymerized unit (M1) of the monomer represented by CX-O-Rf-COOM, the total content of the polymerized unit (1) and the polymerized unit (M1) is preferably 80 to 100 mass%, more preferably 85 mass% or more, still more preferably 90 mass% or more, particularly preferably 99 mass% or more, relative to the total polymerized units constituting the fluoropolymer.
In the case where the polymer (1) contains the polymerized units (1) and polymerized units based on other monomers copolymerizable with the monomer (1), the alternation ratio of the polymerized units (1) to polymerized units based on other monomers copolymerizable with the monomer (1) is preferably 40% or more, more preferably 50% or more, still more preferably 60% or more, still more preferably 70% or more, particularly preferably 80% or more, and most preferably 90% or more. The alternation ratio may be, for example, 40% to 99%. This constitution is based on the general formula CFR in the polymerization unit based on the other monomer copolymerizable with the monomer (1) 11 ＝CR 11 2 The polymerization unit (M) of the monomers shown is particularly preferred.
The alternating ratio of polymerized units (1) in the polymer (1) to polymerized units based on other monomers copolymerizable with the monomer (1) may be determined by the fluoropolymer 19 F-NMR analysis.
The other monomer may be represented by the general formula (n 1-2):
[ chemical 3]
(wherein X is 1 、X 2 The same or different is H or F; x is X 3 H, F, cl, CH of a shape of H, F, cl, CH 3 Or CF (CF) 3 ；X 4 、X 5 The same or differentH or F; a and c are the same or different and are 0 or 1.Rf (radio frequency identification) 3 A fluoroalkyl group having 1 to 40 carbon atoms or a fluoroalkyl group having 2 to 100 carbon atoms and having an ether bond).
Specifically, CH is preferably exemplified 2 ＝CFCF 2 -O-Rf 3 、CF 2 ＝CF-O-Rf 3 、CF 2 ＝CFCF 2 -O-Rf 3 、CF 2 ＝CF-Rf 3 、CH 2 ＝CH-Rf 3 、CH 2 ＝CH-O-Rf 3 (wherein Rf 3 The same as the above formula (n 1-2), and the like.
The other monomer may be represented by the formula (n 2-1):
[ chemical 4]
(wherein X is 9 H, F or CH 3 ；Rf 4 Is a fluoroalkyl group having 1 to 40 carbon atoms or a fluoroalkyl group having 2 to 100 carbon atoms and having an ether bond). The Rf described above 4 Examples of the base include
[ chemical 5]
(wherein Z is 8 H, F or Cl; d1 is an integer of 1 to 4; e1 is an integer of 1 to 10),
-CH(CF 3 ) 2 、
(wherein e2 is an integer of 1 to 5),
(wherein d3 is an integer of 1 to 4, and e3 is an integer of 1 to 10).
The other monomer may be represented by the formula (n 2-2):
CH 2 ＝CHO-Rf 5 (n2-2)
(wherein Rf 5 Is a fluoroalkyl group having 1 to 40 carbon atoms or a fluoroalkyl group having 2 to 100 carbon atoms and having an ether bond).
As the monomer of the formula (n 2-2), specific examples are preferably given
[ chemical 6]
(wherein Z is 9 Is H or F; e4 is an integer of 1 to 10),
(wherein e5 is an integer of 1 to 10),
(wherein e6 is an integer of 1 to 10), and the like.
More specifically, there may be mentioned
[ chemical 7]
CH 2 ＝CHOCH 2 CF 2 CF 2 H、
CH 2 ＝CHOCH 2 CF 2 CF 3 、
CH 2 ＝CHOCH 2 CF 3 、
Etc.
In addition, the general formula (n 2-3) may be mentioned:
CH 2 ＝CHCH 2 O-Rf 6 (n2-3)
(wherein Rf 6 Is a fluorine-containing allyl ether represented by a fluorine-containing alkyl group having 1 to 40 carbon atoms or a fluorine-containing alkyl group having 2 to 100 carbon atoms and having an ether bond, and has the general formula (n 2-4):
CH 2 ＝CH-Rf 7 (n2-4)
(wherein Rf 7 A fluoroalkyl group having 1 to 40 carbon atoms or a fluoroalkyl group having 2 to 100 carbon atoms and having an ether bond), and the like.
As the monomer represented by the general formulae (n 2-3) and (n 2-4), specifically, there may be mentioned
[ chemical 8]
CH 2 ＝CHCH 2 OCH 2 CF 2 CF 2 H、
CH 2 ＝CHCH 2 OCH 2 CF 2 CF 3 、
CH 2 ＝CHCH 2 OCH 2 CF 3 、
And the like.
The content of the polymer (1) is preferably 50 mass% or more, more than 50 mass%, 60 mass% or more, 70 mass% or more, 80 mass% or more, 90 mass% or more, or 99 mass% or more with respect to the total of the polymerized units. The content of the polymerization unit (1) is particularly preferably substantially 100 mass%, and the polymer (1) is most preferably composed of only the polymerization unit (1).
In the polymer (1), the content of polymerized units based on the other monomer copolymerizable with the monomer represented by the general formula (1) is preferably 50 mass% or less, less than 50 mass%, 40 mass% or less, 30 mass% or less, 20 mass% or less, 10 mass% or less, or 1 mass% or less with respect to all polymerized units. The content of the polymerized unit based on the other monomer copolymerizable with the monomer represented by the general formula (1) is particularly preferably substantially 0 mass%, and the polymer (1) most preferably does not contain the polymerized unit based on the other monomer.
The lower limit of the number average molecular weight of the polymer (1) is 0.3X10 in the order of preference 4 Above, 0.4X10 4 Above, 0.5X10 4 Above, 0.7X10 4 Above, 0.8X10 4 Above, 1.0X10 4 Above, 1.2X10 4 Above, 1.4X10 4 、1.6×10 4 Above, 1.8X10 4 Above, 2.0X10 4 Above, 3.0X10 4 The above. The upper limit of the number average molecular weight of the polymer (1) is 75.0X10 in the preferred order 4 The following is 50.0X10 4 Hereinafter, 40.0X10 4 Hereinafter, 30.0X10 4 Hereinafter, 20.0X10 4 The following is given.
The lower limit of the weight average molecular weight of the polymer (1) is 0.4X10 in the preferred order 4 Above, 0.5X10 4 Above, 0.6X10 4 Above, 0.8X10 4 Above, 1.0X10 4 Above, 1.2X10 4 Above, 1.4X10 4 Above, 1.7X10 4 Above, 1.9X10 4 Above, 2.1X10 4 Above, 2.3X10 4 Above, 2.7X10 4 Above, 3.1X10 4 Above, 3.5X10 4 Above, 3.9X10 4 Above, 4.3X10 4 Above, 4.7X10 4 Above, 5.1X10 4 Above, 10.0X10 4 Above, 15.0X10 4 Above, 20.0X10 4 Above, 25.0X10 4 The above. The upper limit of the weight average molecular weight of the polymer (1) is 150.0X10 in the preferred order 4 The following is 100.0X10 4 Hereinafter, 60.0X10 4 The following is 50.0X10 4 Hereinafter, 40.0X10 4 The following is given.
The molecular weight distribution (Mw/Mn) of the polymer (1) is 3.0 or less, 2.7 or less, 2.4 or less, 2.2 or less, 2.0 or less, 1.9 or less, 1.7 or less, 1.5 or less, 1.4 or less, 1.3 or less in the order of preference.
The number average molecular weight and the weight average molecular weight are values obtained by Gel Permeation Chromatography (GPC) using monodisperse polyethylene oxide (PEO) and polyethylene glycol (PEG) as standards. In addition, in the case where measurement by GPC is impossible, the number average molecular weight of the polymer (1) can be obtained from the correlation between the number average molecular weight calculated from the number of terminal groups obtained by NMR, FT-IR or the like and the melt flow rate. The melt flow rate can be measured according to JIS K7210.
The polymer (1) generally has terminal groups. The terminal group is a terminal group formed during polymerization, and representative terminal groups are independently selected from hydrogen, iodine, bromine, a chain or branched alkyl group, and a chain or branched fluoroalkyl group, and may optionally contain at least 1 chain heteroatom. The number of carbon atoms of the alkyl group or the fluoroalkyl group is preferably 1 to 20. These terminal groups are generally formed from the initiator or chain transfer agent used in the formation of the polymer (1) or in a chain transfer reaction.
The polymer (1) preferably has an ion exchange rate (IXR) of 53 or less. IXR is defined above as the number of carbon atoms in the polymer backbone relative to the ionic groups. By hydrolysis to ionic precursor groups (e.g. -SO 2 F) Are not considered ionic groups for determining IXR.
IXR is preferably 0.5 or more, more preferably 1 or more, further preferably 3 or more, further preferably 4 or more, particularly preferably 5 or more, and particularly preferably 8 or more. The IXR is more preferably 43 or less, still more preferably 33 or less, and particularly preferably 23 or less.
As the ion exchange capacity of the polymer (1), it is preferably 0.80meq/g or more, 1.50meq/g or more, 1.75meq/g or more, 2.00meq/g or more, 2.20meq/g or more, more than 2.20meq/g, 2.50meq/g or more, 2.60meq/g or more, 3.00meq/g or more, 3.20meq/g or more, 3.50meq/g or more, in this order. The ion exchange capacity is the content of ionic groups (anionic groups) of the polymer (1), and is obtained by calculating the composition of the polymer (1).
In the polymer (1), the ionic groups (anionic groups) are typically distributed along the polymer main chain. The polymer (1) preferably comprises a polymer main chain and recurring side chains bonded to the main chain, the side chains preferably having an ionic group.
The polymer (1) preferably has water solubility. Water-solubility refers to the property of being readily dissolved or dispersed in an aqueous medium. The polymer having water solubility cannot be measured for particle size by Dynamic Light Scattering (DLS) or shows particle size of 10nm or less, for example.
The polymer (1) preferably has sufficient water solubility. In general, the higher the content of the polymer (1) in the aqueous solution, the more difficult it is for the polymer (1) to be sufficiently dissolved or dispersed in the aqueous medium. Therefore, it can be said that even when the content of the polymer (1) in the aqueous solution is high, the water solubility of the polymer (1) whose particle diameter cannot be measured by the dynamic light scattering method (DLS) is high. The polymer (1) preferably cannot be measured in terms of particle diameter even when contained in an aqueous solution at a content of 1.0 mass%. Even when the polymer (1) is contained in the aqueous solution at a content of 1.5 mass%, more preferably at a content of 2.0 mass%, the particle diameter cannot be measured.
The viscosity of the aqueous solution of the polymer (1) is preferably 5.0mpa.s or more, more preferably 8.0mpa.s or more, still more preferably 10.0mpa.s or more, particularly preferably 12.0mpa.s or more, most preferably 14.0mpa.s or more, preferably 100.0mpa.s or less, still more preferably 50.0mpa.s or less, still more preferably 25.0mpa.s or less, and particularly preferably 20.0mpa.s or less.
The viscosity of the aqueous solution of the polymer (1) can be determined by adjusting the content of the polymer (1) in the aqueous solution to 33 mass% with respect to the aqueous solution and measuring the viscosity of the resulting aqueous solution at 20℃using a tuning fork vibration viscometer (model: SV-10) manufactured by A & D company.
The Critical Micelle Concentration (CMC) of the polymer (1) is preferably 0.1 mass% or more, more preferably 0.5 mass% or more, further preferably 1 mass% or more, preferably 20 mass% or less, more preferably 10 mass% or less, further preferably 5 mass% or less.
The critical micelle concentration of the polymer (1) can be determined by measuring the surface tension. The surface tension can be measured, for example, by using a surface tensiometer CBVP-A3 manufactured by Kyowa Kagaku Co., ltd.
The acid value of the polymer (1) is preferably 60 or more, more preferably 90 or more, further preferably 120 or more, particularly preferably 150 or more, most preferably 180 or more, and the upper limit is not particularly limited, but is preferably 300 or less.
Regarding the acid value of the polymer (1), the polymer (1) has-SO 3 -SO other than H 3 M, i.e. -SO 3 M (M is a metal atom, -NR) 7 4 Imidazolium with or without substituents, pyridinium with or without substituents, or phosphonium with or without substituents), can be used as a catalyst 3 Conversion of M to-SO 3 After H, pass-SO 3 Acid-base titration of H.
The polymer (1) can be produced by a production method for producing the polymer (1) by polymerizing the polymer (1).
The oxygen concentration in the reaction system of the polymerization is preferably 1500 ppm by volume or less, more preferably 500 ppm by volume or less, still more preferably 100 ppm by volume or less, particularly preferably 50 ppm by volume or less, from the viewpoint that the polymer (1) having a higher molecular weight can be easily produced. The oxygen concentration in the reaction system is usually 0.01 ppm by volume or more. In the above production method, the oxygen concentration in the reaction system is preferably maintained within the above range throughout the polymerization of the polymer (1).
The oxygen concentration in the polymerization reaction system can be controlled, for example, by passing an inert gas such as nitrogen or argon, or, in the case of using a gaseous monomer, by passing the gaseous monomer into a liquid phase or a gas phase in the reactor. The oxygen concentration in the polymerization reaction system can be determined by measuring and analyzing the gas discharged from the exhaust line of the polymerization system by a low-concentration oxygen analyzer.
The polymerization temperature of the polymer (1) is preferably 70℃or lower, more preferably 65℃or lower, still more preferably 60℃or lower, still more preferably 55℃or lower, particularly preferably 50℃or lower, particularly preferably 45℃or lower, most preferably 40℃or lower, preferably 10℃or higher, more preferably 15℃or higher, still more preferably 20℃or higher, from the viewpoint that the polymer (1) having a higher molecular weight can be easily produced.
In the above production method, the polymer (1) may be copolymerized with the other monomer.
In the above production method, the polymerization may be carried out in the presence of a pH adjuster. The pH adjustor can be added before the polymerization is started or after the polymerization is started.
As the pH adjuster, ammonia, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, ammonium carbonate, sodium bicarbonate, potassium bicarbonate, ammonium bicarbonate, sodium phosphate, potassium phosphate, sodium citrate, potassium citrate, ammonium citrate, sodium gluconate, potassium gluconate, ammonium gluconate, and the like can be used. The pH can be measured by a pH meter manufactured by orion corporation.
The polymerization pressure is usually from atmospheric pressure to 10MPaG. The polymerization pressure is appropriately determined depending on the kind of the monomer used, the molecular weight of the target polymer (1), and the reaction rate.
The polymerization time is usually 1 to 200 hours, and may be 5 to 100 hours.
In the above production method, the polymerization of the monomer (1) may be carried out in an aqueous medium or in the absence of an aqueous medium. The polymerization of the monomer (1) may be carried out in the absence of an aqueous medium and in the presence of a nonaqueous medium (for example, an organic solvent such as toluene) in an amount of less than 10% by mass relative to the amount of the monomer containing the monomer (1). The polymerization of the monomer (1) may be emulsion polymerization or suspension polymerization, or may be bulk polymerization.
The aqueous medium is a reaction medium for allowing polymerization to proceed, and is a liquid containing water. The aqueous medium is not particularly limited as long as it contains water, and may contain water and a non-fluorine-containing organic solvent such as alcohol, ether, ketone, or the like and/or a fluorine-containing organic solvent having a boiling point of 40 ℃ or less. As the aqueous medium, water is preferable.
In the above production method, the polymerization of the polymer (1) can be performed in the presence of a polymerization initiator. The polymerization initiator is not particularly limited as long as it can generate radicals in the above-mentioned polymerization temperature range, and known oil-soluble and/or water-soluble polymerization initiators can be used. Further, the polymerization may be initiated in a redox form in combination with a reducing agent or the like. The concentration of the polymerization initiator is appropriately determined depending on the kind of the monomer, the molecular weight of the target polymer (1), and the reaction rate. In the case of polymerizing the monomer (1) in an aqueous medium, a water-soluble polymerization initiator such as persulfate is preferably used. In the case where the polymerization of the monomer (1) is carried out in the absence of an aqueous medium, an oil-soluble polymerization initiator such as peroxide is preferably used.
As the polymerization initiator, organic peroxides such as persulfates (e.g., ammonium persulfate), disuccinic acid peroxide, and dipentaerythritol peroxide may be used alone or in the form of a mixture of these. Alternatively, the catalyst may be used in combination with a reducing agent such as sodium sulfite to prepare a redox system. Further, a radical scavenger such as hydroquinone or catechol, or a decomposition agent such as a peroxide such as ammonium sulfite may be added to adjust the radical concentration in the system during the polymerization.
As the polymerization initiator, persulfate is preferable among them, since the polymer (1) having a higher molecular weight can be easily produced. The persulfate may be ammonium persulfate, potassium persulfate, sodium persulfate, or the like, and ammonium persulfate is preferable.
As the polymerization initiator, an oil-soluble radical polymerization initiator can be used. The oil-soluble radical polymerization initiator may be a known oil-soluble peroxide, and the following peroxides are exemplified as typical examples: dialkyl peroxycarbonates such as diisopropyl peroxydicarbonate and di-sec-butyl peroxydicarbonate; peroxyesters such as t-butyl peroxyisobutyrate and t-butyl peroxypivalate; dialkyl peroxides such as di-t-butyl peroxide; di (ω -hydro-dodecafluorohexanoyl) peroxide, di (ω -hydro-tetradecahaloyl) peroxide, di (ω -hydro-hexadecanoyl) peroxide, di (perfluorobutanoyl) peroxide, di (perfluoropentanoyl) peroxide, di (perfluorohexanoyl) peroxide, di (perfluoroheptanoyl) peroxide, di (perfluorooctanoyl) peroxide, di (perfluorononanoyl) peroxide, di (ω -chloro-hexafluorobutanoyl) peroxide, di (ω -chloro-decafluorohexanoyl) peroxide, di (ω -chloro-tetradecanoyl) peroxide, ω -hydro-dodecafluoroheptanoyl- ω -hexadecanoyl-peroxide, ω -chloro-hexafluorobutanoyl- ω -chloro-decafluorodecanoyl-peroxide, ω -hydrododecafluoroheptanoyl-perfluoroheptanoyl-peroxide, di (dichloro-penta-fluoropentanoyl) peroxide, di (trichlorooctahexanoyl) peroxide, di (tetrafluoroundecanoyl) peroxide, di (ω -chloro-dodecafluorodecanoyl) peroxide, di (dichloro-dodecanoyl) or di (fluoro-dodecanoyl) such as di (ω -chloro-dodecafluoroheptanoyl) peroxide; etc.
The amount of the polymerization initiator to be added is not particularly limited, and may be at least an amount (for example, several ppm relative to the concentration of water) at one time, sequentially or continuously at the initial stage of polymerization, to such an extent that the polymerization rate does not significantly decrease. The upper limit is a range in which heat removal from the apparatus surface can be performed by using the polymerization reaction heat and the reaction temperature can be increased, and the upper limit is more preferably a range in which the polymerization reaction heat can be removed from the apparatus surface.
In the above production method, the polymerization initiator may be added at the start of the polymerization, and the polymerization initiator may be added at the same time during the polymerization. The ratio of the amount of the polymerization initiator added at the start of polymerization to the amount of the polymerization initiator added during polymerization is preferably 95/5 to 5/95, more preferably 60/40 to 10/90, still more preferably 30/70 to 15/85. The method of adding the polymerization initiator to the polymerization is not particularly limited, and the polymerization initiator may be added in a single amount, may be added in two or more portions, or may be added continuously.
In the above production method, since the polymer (1) having a higher molecular weight can be easily produced, the total amount of the polymerization initiator to be used in the polymerization is preferably 0.00001 to 10% by mass based on the aqueous medium. The total amount of the polymerization initiator to be added in the polymerization is preferably 0.0001% by mass or more, more preferably 0.001% by mass or more, still more preferably 0.01% by mass or more, preferably 5% by mass or less, and still more preferably 2% by mass or less.
In the above production method, since the polymer (1) having a higher molecular weight can be easily produced, the total amount of the polymerization initiator to be added for polymerization is preferably 0.001 mol% to 10 mol% relative to the total amount of the monomer to be added for polymerization. The total amount of the polymerization initiator to be added in the polymerization is preferably 0.005 mol% or more, more preferably 0.01 mol% or more, particularly preferably 0.1 mol% or more, most preferably 0.5 mol% or more, more preferably 10 mol% or less, more preferably 5.0 mol% or less, particularly preferably 2.5 mol% or less, particularly most preferably 2.2 mol% or less, and most preferably 2.0 mol% or less.
In the above production method, since the polymer (1) having a higher molecular weight can be easily produced, the amount of the monomer containing the polymer (1) at the start of polymerization is preferably 20 mass% or more relative to the amount of the aqueous medium. The amount of the monomer is more preferably 30% by mass or more, still more preferably 40% by mass or more. The upper limit of the amount of the monomer to be present is not particularly limited, but may be 200 mass% or less in terms of facilitating the progress of the polymerization. The amount of the monomer at the start of polymerization is the total amount of the polymer (1) present in the reactor at the start of polymerization and other monomers in the case of the presence.
When the polymerization of the monomer (1) is carried out in the absence of an aqueous medium, the total amount of the polymerization initiator such as peroxide is preferably 0.001 mol% to 10 mol% based on the total amount of the monomer (monomer mixture) containing the monomer (1). The total amount of the polymerization initiator to be added in the polymerization is preferably 0.005 mol% or more, more preferably 0.01 mol% or more, still more preferably 10 mol% or less, still more preferably 5.0 mol% or less, particularly preferably 2.5 mol% or less, particularly most preferably 2.2 mol% or less, and still more preferably 2.0 mol% or less.
The polymerization of the polymer (1) can be carried out as follows: the above polymerization is carried out by charging the polymer (1), and if necessary, an aqueous medium, other monomers, and if necessary, other additives into a reactor, stirring the contents of the reactor, maintaining the reactor at a prescribed polymerization temperature, and then adding a prescribed amount of a polymerization initiator to initiate polymerization. After the polymerization reaction starts, monomers, polymerization initiators, and other additives may be added according to the purpose.
The polymer (1) used in the production method of the present invention contains substantially no dimers or trimers of the monomer (1). Dimers and trimers of monomer (1) are usually produced when monomer (1) is polymerized to give polymer (1). The content of the dimer and trimer in the polymer (1) is 1.0% by mass or less, preferably 0.1% by mass or less, more preferably 0.01% by mass or less, further preferably 0.001% by mass or less, particularly preferably 0.0001% by mass or less, relative to the polymer (1).
The polymer (1) used in the production method of the present invention may be a polymer substantially free of dimers and trimers composed of polymerized units (1) based on the monomer (1) and polymerized units based on other monomers copolymerizable with the monomer (1). Dimers and trimers composed of polymerized units (1) and polymerized units based on other monomers are generally produced when the monomer (1) is polymerized with other monomers copolymerizable with the monomer (1) to give the polymer (1). The content of the dimer and trimer composed of the polymerized unit (1) and the polymerized unit based on another monomer in the polymer (1) is 1.0% by mass or less, preferably 0.1% by mass or less, more preferably 0.01% by mass or less, still more preferably 0.001% by mass or less, and particularly preferably 0.0001% by mass or less, relative to the polymer (1).
The content of the dimer and the trimer in the polymer (1) can be specified by performing Gel Permeation Chromatography (GPC) analysis of the polymer (1) and calculating the ratio (area percentage) of the total of the peak areas of the dimer and the trimer to the total area of the peaks of the chromatogram obtained by GPC analysis.
In addition, in the case where the content of the dimer and trimer in the polymer (1) is less than 0.5 mass% with respect to the polymer (1), it can be specified by measurement using liquid chromatography-mass spectrometry (LC/MS).
Specifically, an aqueous solution of the monomer (1) was prepared at a content of 5 or more levels, each content was subjected to LC/MS analysis, and the relationship between the content and the area of the region (integrated value of the peak) with respect to the content was plotted, to prepare a calibration curve of the monomer (1). Further, a calibration curve of the dimer and trimer of the monomer (1) was prepared from the calibration curve of the monomer (1).
Methanol was added to the polymer (1) to prepare a mixture, which was filtered using an ultrafiltration disk (molecular weight cut-off: 3000 Da), and the obtained recovered liquid was subjected to LC/MS analysis.
Then, using the calibration curve, the area of the region of the chromatogram of the dimer and trimer of the monomer (1) (the integrated value of the peak) can be converted into the content of the dimer and trimer.
The content of the component having a molecular weight of 3000 or less in the polymer (1) may be 3.7% or less, preferably 3.2% or less, more preferably 2.7% or less, still more preferably 1.7% or less, particularly preferably 1.2% or less, particularly preferably 1.0% or less, and most preferably 0.5% or less, based on the polymer (1). The lower limit of the content of the component having a molecular weight of 3000 or less is not limited, and is, for example, 0.01%. The content of the component having a molecular weight of 3000 or less can be calculated by the peak area of GPC. The component having a molecular weight of 3000 or less contains all compounds having a molecular weight of 3000 or less.
The content of the component having a molecular weight of 2000 or less in the polymer (1) may be 3.2% or less, preferably 2.7% or less, more preferably 2.2% or less, still more preferably 1.7% or less, particularly preferably 1.2% or less, and particularly preferably 0.6% or less, based on the polymer (1). The lower limit of the content of the component having a molecular weight of 2000 or less is not limited, and is, for example, 0.01%. The content of the component having a molecular weight of 2000 or less can be calculated by the peak area of GPC. The component having a molecular weight of 2000 or less contains all compounds having a molecular weight of 2000 or less.
The content of the component having a molecular weight of 1500 or less in the polymer (1) may be 2.7% or less, preferably 2.2% or less, more preferably 1.7% or less, still more preferably 1.2% or less, and particularly preferably 0.6% or less, with respect to the polymer (1). The lower limit of the content of the component having a molecular weight of 1500 or less is not limited, and is, for example, 0.01%. The content of the component having a molecular weight of 1500 or less can be calculated by the peak area of GPC. The component having a molecular weight of 1500 or less contains all compounds having a molecular weight of 1500 or less.
The content of the component having a molecular weight of 1000 or less in the polymer (1) may be 2.2% or less, preferably 1.7% or less, more preferably 1.2% or less, and still more preferably 0.6% or less with respect to the polymer (1). The lower limit of the content of the component having a molecular weight of 1000 or less is not limited, and is, for example, 0.01%. The content of the component having a molecular weight of 1000 or less can be calculated by the peak area of GPC. The component having a molecular weight of 1000 or less contains all compounds having a molecular weight of 1000 or less.
In the polymerization of a perfluorinated monomer in an aqueous medium, a polymer (1) substantially free of dimers and trimers of the monomer (1) is used to produce a fluoropolymer substantially free of dimers and trimers of the monomer (1).
The polymer (1) is a polymer comprising polymerized units (1) based on the monomer (1). The polymer (1) used in the present invention is a polymer in which a dimer (a polymer comprising 2 polymerization units (1)) and a trimer (a polymer comprising 3 polymerization units (1)) are substantially removed from the polymer (1) comprising 2 or more polymerization units (1).
In the polymerization of a perfluorinated monomer in an aqueous medium, by using a polymer (1) that is substantially free of dimers and trimers composed of polymerized units (1) based on the monomer (1) and polymerized units based on other monomers copolymerizable with the monomer (1), even in the case of using a polymer (1) containing polymerized units (1) and polymerized units based on other monomers as the polymer (1), a fluorine-containing polymer that is substantially free of dimers and trimers composed of polymerized units (1) and polymerized units based on other monomers can be produced.
The molecular weight of the monomer (1) is preferably 500 or less, more preferably 400 or less. That is, the polymer (1) preferably contains substantially no dimers or trimers having a molecular weight of 1500 or less, and more preferably contains substantially no dimers or trimers having a molecular weight of 1200 or less.
Accordingly, the manufacturing method of the present invention preferably includes: a step of polymerizing a monomer (1) represented by the general formula (1) to obtain a crude composition containing a polymer of the monomer (1); and removing the dimer and trimer of the monomer (1) contained in the crude composition from the crude composition to obtain a polymer (1) having a content of the dimer and trimer of the monomer (1) of 1.0 mass% or less with respect to the polymer (1).
The polymerization of the monomer (1) can be carried out by the above-mentioned method. By producing a crude composition by this method, a crude composition in which the polymer (1) is dispersed or dissolved in an aqueous medium can be obtained.
The polymerization of the monomer (1) is preferably carried out in an aqueous medium in the substantial absence of a fluorosurfactant (excluding the monomer (1) represented by the general formula (1)).
In the present invention, "in the substantial absence of a fluorosurfactant" means that the amount of the fluorosurfactant relative to the aqueous medium is 10 mass ppm or less. The amount of the fluorosurfactant relative to the aqueous medium is preferably 1 ppm by mass or less, more preferably 100 ppb by mass or less, still more preferably 10 ppb by mass or less, and still more preferably 1 ppb by mass or less.
The fluorosurfactant is described in the following description of polymerization of perfluoromonomers.
The crude composition thus obtained generally contains more than 1.0 mass% of dimers and trimers of the monomer (1) relative to the total mass of the polymer. The content of the dimer and trimer of the monomer (1) in the polymer may be, for example, 2.0 mass% or more, 3.0 mass% or more, 30.0 mass% or less, or 20.0 mass% or less with respect to the polymer of the monomer (1).
In addition, when polymerization of the monomer (1) and other monomer copolymerizable with the monomer (1) is performed, a dimer and a trimer composed of polymerized units (1) based on the monomer (1) and polymerized units based on other monomer copolymerizable with the monomer (1) are generally contained in an amount exceeding 1.0 mass% relative to the total mass of the polymer in the resulting crude composition. The content of the dimer and trimer composed of the polymerized unit (1) and the polymerized unit based on the other monomer may be, for example, 2.0% by mass or more, 3.0% by mass or more, 30.0% by mass or less, or 20.0% by mass or less with respect to the polymer.
The content of the dimer and trimer in the crude composition can be specified by performing Gel Permeation Chromatography (GPC) analysis of the crude composition, and calculating the ratio (area percentage) of the total of the peak areas of the dimer and trimer to the total area of each peak of the chromatogram obtained by GPC analysis.
Next, dimers and trimers of the monomer (1) contained in the crude composition obtained by polymerization of the monomer (1), or dimers and trimers composed of the polymerized unit (1) and polymerized units based on other monomers, are removed from the crude composition. The means for removing the dimer and the trimer is not particularly limited, and at least 1 means selected from the group consisting of ultrafiltration, microfiltration, dialysis membrane treatment, liquid separation and reprecipitation is preferable, at least 1 means selected from the group consisting of ultrafiltration, microfiltration, liquid separation and reprecipitation is more preferable, at least 1 means selected from the group consisting of ultrafiltration and liquid separation is further more preferable, and ultrafiltration is particularly preferable.
By appropriately selecting the means for removing the dimer and trimer, a component having a molecular weight of 3000 or less, a component having a molecular weight of 2000 or less, a component having a molecular weight of 1500 or less, and a component having a molecular weight of 1000 or less can be removed.
The dimer and trimer of the monomer (1) are produced by polymerization of the monomer (1), and as a result, the dimer and trimer of the monomer (1) are contained in the polymer (1), which has not been known heretofore. The mechanism of formation of dimers and trimers of monomer (1) is not necessarily clear, but is presumed to be: particularly, among the monomers existing in the polymerization system, dimerization and trimerization of the monomer (1) occur at a non-negligible frequency by the polymerization reaction in the polymerization system in which the monomer (1) is a majority.
In removing dimers and trimers, usually, unreacted monomer (1) is also removed from the crude composition at the same time. Even in the case where the unreacted monomer (1) is introduced into PTFE by polymerization, it is not necessarily detrimental to the function of PTFE, and therefore the unreacted monomer (1) is not necessarily removed. However, by removing the unreacted monomer (1) simultaneously with the dimer and the trimer in advance, the amount of the monomer to be polymerized can be calculated irrespective of the presence of the unreacted monomer (1), and there is an advantage that a fluoropolymer having a desired monomer composition can be easily produced. Even when the monomer (1) remains in the polymer (1) or when the monomer (1) is newly added as a comonomer, the dimerization and trimerization of the monomer (1) are not substantially performed by the polymerization reaction in the polymerization system in which TFE occupies a large part of the polymerization system among the monomers existing in the polymerization system, and the dimer and trimer of the monomer (1) hardly remain in the obtained fluoropolymer.
The crude composition obtained by polymerization of the monomer (1) may be a polymerized composition obtained during the polymerization, may be a composition obtained by diluting or concentrating a polymerized composition obtained during the polymerization, or may be a composition subjected to dispersion stabilization treatment or the like. In order to smoothly perform ultrafiltration, microfiltration or dialysis membrane treatment, the viscosity of the crude composition is also preferably adjusted by these treatments.
The content of the polymer of the monomer (1) in the crude composition is not particularly limited, and may be, for example, 0.1 to 20% by mass. The content of the polymer of the monomer (1) in the crude composition is preferably 18.0% by mass or less, more preferably 15.0% by mass or less, further preferably 12.0% by mass or less, particularly preferably 10.0% by mass or less, preferably 0.5% by mass or more, more preferably 1.0% by mass or more, further preferably 1.2% by mass or more, particularly preferably 1.5% by mass or more, and most preferably 2.0% by mass or more, in terms of the removal efficiency of the dimer and trimer. The content of the polymer of the monomer (1) in the crude composition can be adjusted, for example, by a method of adding water to the crude composition obtained by polymerization of the monomer (1), a method of concentrating the crude composition obtained by polymerization of the monomer (1), or the like.
The pH of the crude composition is preferably from-7.0 to 11.0, more preferably from-6.0 to 8.0, and even more preferably from-5.0 to 7.0. The pH of the crude composition can be adjusted by adding a pH adjuster to the crude composition obtained by polymerization of the monomer (1). The pH adjuster may be an acid or a base, and examples thereof include phosphate, sodium hydroxide, potassium hydroxide, and ammonia water.
In the case of performing ultrafiltration, microfiltration or dialysis membrane treatment, the viscosity of the crude composition is preferably 25mpa·s or less because these treatments are smoothly performed. The viscosity of the crude composition can be adjusted, for example, by a method of adjusting the number average molecular weight of the polymer of the monomer (1), a method of adjusting the concentration of the polymer of the monomer (1) in the crude composition, a method of adjusting the temperature of the crude composition, or the like.
The ultrafiltration or microfiltration may be a cross-flow method or a dead-end method, and is not limited, but a cross-flow method is preferable in terms of reducing clogging of the membrane.
The ultrafiltration may be performed using an ultrafiltration membrane. The ultrafiltration can be performed using, for example, an ultrafiltration device having an ultrafiltration membrane, and a centrifugal ultrafiltration method, a batch ultrafiltration method, a cyclic ultrafiltration method, or the like can be used.
The ultrafiltration membrane generally has a molecular weight cut-off of 0.1X10 4 Da～30×10 4 Da. The ultrafiltration membrane preferably has a molecular weight cut-off of 0.3X10 since clogging of the membrane can be suppressed and dimers and trimers can be effectively reduced 4 Da above. The molecular weight cut-off is more preferably 0.5X10 4 Da or more, particularly preferably 0.6X10) 4 Da or more, most preferably 0.8X10 4 Da above. The molecular weight cut-off may also be 1.0×10 4 Da above. In addition, the molecular weight cut-off is preferably 20X 10 in terms of the removal efficiency of dimers and trimers 4 Da or less, more preferably 10X 10 4 Da or less.
Regarding the molecular weight cut-off of the ultrafiltration membrane, for example, polystyrene having a known weight average molecular weight may be passed through the membrane, and a molecular weight capable of preventing 90% may be used as the molecular weight cut-off. The polystyrene can be quantified using gel permeation chromatography.
The shape of the ultrafiltration membrane is not limited to a known shape, and examples thereof include a hollow fiber type, a flat membrane type, a spiral type, and a tube type. From the viewpoint of suppressing clogging, a hollow fiber type is preferable.
The inner diameter of the hollow fiber type ultrafiltration membrane is not particularly limited, and may be, for example, 0.1mm to 2mm. Preferably 0.8mm to 1.4mm.
The length of the hollow fiber type ultrafiltration membrane is not limited, and may be, for example, 0.05m to 3m. Preferably 0.05m to 2m.
The material of the ultrafiltration membrane is not particularly limited, and examples thereof include organic materials such as cellulose, cellulose ester, polysulfone, sulfonated polysulfone, polyether sulfone, sulfonated polyether sulfone, chlorinated polyethylene, polypropylene, polyolefin, polyvinyl alcohol, polymethyl methacrylate, polyacrylonitrile, polyvinylidene fluoride, polytetrafluoroethylene, and other organic materials, metals such as stainless steel, and other inorganic materials.
The ultrafiltration membrane is preferably made of an organic material, more preferably chlorinated polyethylene, polypropylene, polyvinylidene fluoride, polytetrafluoroethylene, polyacrylonitrile, polysulfone or polyethersulfone, and even more preferably polyacrylonitrile, polysulfone or polyvinylidene fluoride.
Specific examples of the ultrafiltration membrane include type G-5, type G-10, type G-20, type G-50, type PW, and type HWS UF of DESAL; KOCH company HFM-180, HFM-183, HFM-251, HFM-300, HFM-116, HFM-183, HFM-300, HFK-131, HFK-328, MPT-U20, MPS-U20P, MPS-U20S; SPE1, SPE3, SPE5, SPE10, SPE30, SPV5, SPV50, SOW30 from syncer corporation; a Microza (registered trademark) UF series manufactured by Asahi chemical Co., ltd; NTR7410 manufactured by Ridong electric company, etc.
The ultrafiltration is preferably performed at a pressure of 0.01MPa or more in terms of the removal efficiency of the dimer and trimer. More preferably 0.03MPa or more, still more preferably 0.05MPa or more. In view of pressure resistance, the pressure is preferably 0.5MPa or less, more preferably 0.25MPa or less, and still more preferably 0.2MPa or less.
The ultrafiltration is preferably performed at a flow rate of 10 mL/min or more, more preferably 50 mL/min or more, and further preferably at a flow rate of 5000 mL/min or less, more preferably 1000 mL/min or less, from the viewpoint of the removal efficiency of the dimer and trimer.
The microfiltration may be performed using a microfiltration membrane. Microfiltration membranes typically have an average pore size of 0.05 μm to 1.0 μm.
The average pore diameter of the microfiltration membrane is preferably 0.1 μm or more because of the effective removal of dimers and trimers. More preferably 0.075 μm or more, still more preferably 0.1 μm or more. The average pore diameter is preferably 1.00 μm or less. The average pore diameter is more preferably 0.50 μm or less, and still more preferably 0.25 μm or less.
The average pore size of the microfiltration membrane can be measured according to ASTM F316 (bubble point method).
The shape of the microfiltration membrane is not limited to a known shape, and examples thereof include a hollow fiber type, a flat membrane type, a spiral type, and a tube type. From the viewpoint of suppressing clogging, a hollow fiber type is preferable.
The inner diameter of the hollow fiber type microfiltration membrane is not particularly limited, and may be, for example, 0.1mm to 2mm. Preferably 0.8mm to 1.4mm.
The length of the hollow fiber type microfiltration membrane is not particularly limited, and may be, for example, 0.05m to 3m. Preferably 0.05m to 2m.
Examples of the material of the microfiltration membrane include cellulose, aromatic polyamide, polyvinyl alcohol, polysulfone, polyethersulfone, polyvinylidene fluoride, polyethylene, polyacrylonitrile, polypropylene, polycarbonate, polytetrafluoroethylene, ceramic, metal, and the like. Among them, aromatic polyamide, polyvinyl alcohol, polysulfone, polyvinylidene fluoride, polyethylene, polyacrylonitrile, polypropylene, polycarbonate or polytetrafluoroethylene is preferable, and polyacrylonitrile or polyvinylidene fluoride is particularly preferable.
Specific examples of the microfiltration membrane include Cefilt manufactured by japan insulator company; the Microza U series and Microza P series manufactured by Asahi chemical Co., ltd; poreulon SPMW, poreulon OPMW, poreulon PM manufactured by Sumitomo electric company; trefil manufactured by dori corporation; NADIR MP005 and NADIR MV020 manufactured by MICRODYN-NADIR Co; x-flow manufactured by Norit corporation, and the like.
The microfiltration is preferably carried out at a pressure of 0.01MPa or more in terms of the removal efficiency of the dimer and trimer. More preferably 0.03MPa or more, still more preferably 0.05MPa or more. In view of pressure resistance, the pressure is preferably 0.5MPa or less, more preferably 0.25MPa or less, and still more preferably 0.2MPa or less.
The microfiltration is preferably performed at a flow rate of 10 mL/min or more, more preferably 50 mL/min or more, and further preferably 5000 mL/min or less, more preferably 1000 mL/min or less, from the viewpoint of the removal efficiency of the dimer and trimer.
The dialysis membrane treatment is performed using a dialysis membrane. Dialysis membranes typically have a pore size of 0.05X10 4 Da～100×10 4 Molecular weight cut-off of Da.
The dialysis membrane preferably has a molecular weight cut-off of 0.3X10 because of the ability to inhibit clogging of the membrane and to effectively remove dimers and trimers 4 Da above. The molecular weight cut-off is more preferably 0.5X10 4 Da or more, more preferably 1.0X10) 4 Da or more, and more preferably 1.5X10 4 Da or more, particularly preferably 2.0X10 4 Da or more, particularly preferably 3.0X10) 4 Da or more, most preferably 5.0X10 4 Da above. The molecular weight cut-off may also be 8.0X10 4 Da above.
In addition, from the aspect of the removal efficiency of dimers and trimers, the following appliesThe molecular weight cut-off is preferably 20X 10 4 Da or less, more preferably 10X 10 4 Da or less.
The molecular weight cut-off of the dialysis membrane can be measured by the same method as that of the ultrafiltration membrane.
The material of the dialysis membrane is not particularly limited, and examples thereof include cellulose, polyacrylonitrile, polymethyl methacrylate, ethylene vinyl alcohol copolymer, polysulfone, polyamide, and polyester-based polymer alloy.
Specific examples of the Dialysis membrane include Spectra/Por (registered trademark) flow-A-Lyzer, tube-A-Lyzer, dialyzed piping, 6 Dialyzed piping, and 7 Dialyzed piping manufactured by Spectrum Laboratories.
The ultrafiltration, microfiltration or dialysis membrane treatment is preferably carried out at a temperature of 10℃or higher. More preferably 15℃or higher, still more preferably 20℃or higher, and particularly preferably 30℃or higher. By setting the temperature to the above range, dimers and trimers can be reduced more efficiently. The temperature is preferably 90℃or lower, more preferably 80℃or lower, still more preferably 70℃or lower, particularly preferably 60℃or lower.
The ultrafiltration, microfiltration or dialysis membrane treatment may be performed while adding water to the crude composition or adjusting the pH of the crude composition. The water may be added to the crude composition intermittently or continuously.
The end point of the ultrafiltration, microfiltration or dialysis membrane treatment is not limited as long as it is appropriately determined. In the ultrafiltration, microfiltration or dialysis membrane treatment, the filtration membrane may be backwashed with water once or so based on a filtration time of 1 to 24 hours in order to improve the durability of the filtration membrane.
The separation can be carried out, for example, by adding an organic solvent to the composition, separating the composition into two phases, i.e., an aqueous phase and an organic solvent phase, and recovering the aqueous phase.
Reprecipitation can be carried out, for example, as follows: the composition is added dropwise to a poor solvent to precipitate a polymer, the precipitated polymer is recovered, the recovered polymer is dissolved in the poor solvent, the resulting solution is added dropwise to the poor solvent to reprecipitate the polymer, and the precipitated polymer is recovered.
By removing dimers and trimers of the monomer (1) from a crude composition of the polymer containing the monomer (1), generally, an aqueous solution containing the polymer (1) substantially free of dimers and trimers is obtained. The polymer (1) used in the production method of the present invention may be the polymer (1) contained in the aqueous solution obtained, or may be the polymer (1) separated from the aqueous solution. The method for separating the polymer (1) from the aqueous solution is not particularly limited. For example, the polymer (1) may be separated by a method of precipitating, washing, drying, or the like the polymer (1) in an aqueous solution.
As the polymer (1), an aqueous solution containing the polymer (1) can be used. The preferable content of the dimer and trimer of the monomer (1) or the preferable content of the dimer and trimer composed of the polymerized unit (1) and the polymerized unit based on the other monomer with respect to the polymer (1) in the aqueous solution is as described above.
< polymerization of perfluoromonomer >
In the production method 1 of the present invention, a perfluoro monomer is polymerized in an aqueous medium in the presence of the polymer (1), thereby obtaining a fluoropolymer. The content of the polymerized units based on the perfluorinated monomer in the obtained fluoropolymer is 90 mol% or more relative to the total polymerized units of the fluoropolymer.
As perfluorinated monomers, preference is given to having at least 1 double bond. The perfluoro monomer is preferably at least 1 selected from the group consisting of tetrafluoroethylene [ TFE ], hexafluoropropylene [ HFP ], perfluoro (alkyl vinyl ether) and perfluoro (alkyl allyl ether).
The perfluoro (alkyl vinyl ether) is preferably at least 1 selected from the group consisting of, for example, the following fluorine-containing monomers:
general formula (110): CF (compact flash) 2 ＝CF-ORf 111
(wherein Rf 111 Represents a perfluorinated organic group), a fluorine-containing monomer represented by the formula,
General formula (130): CF (compact flash) 2 ＝CFOCF 2 ORf 131
(wherein Rf 131 Is a linear or branched perfluoroalkyl group having 1 to 6 carbon atoms, a cyclic perfluoroalkyl group having 5 to 6 carbon atoms, a linear or branched perfluorooxyalkyl group having 2 to 6 carbon atoms containing 1 to 3 oxygen atoms), a fluorine-containing monomer represented by,
General formula (140): CF (compact flash) 2 ＝CFO(CF 2 CF(Y 141 )O) m (CF 2 ) n F
(wherein Y is 141 Represents a fluorine atom or a trifluoromethyl group. m is an integer of 1 to 4. n is an integer of 1 to 4), and a fluorine-containing monomer represented by the formula (I)
General formula (150): CF (compact flash) 2 ＝CF-O-(CF 2 CFY 151 -O) n -(CFY 152 ) m -A 151
(wherein Y is 151 Represents fluorine atom, -SO 2 F group or perfluoroalkyl group. Perfluoroalkyl groups may contain etheric oxygen and-SO 2 And F base. n represents an integer of 0 to 3. n Y' s 151 May be the same or different. Y is Y 152 Represents fluorine atoms or-SO 2 And F base. m represents an integer of 1 to 5. m Y' s 152 May be the same or different. A is that 151 Representation of-SO 2 X 151 、-COZ 151 or-POZ 152 Z 153 。X 151 Representation F, cl, br, I, -OR 151 or-NR 152 R 153 。Z 151 、Z 152 And Z 153 Identical or different, representing-NR 154 R 155 OR-OR 156 。R 151 、R 152 、R 153 、R 154 、R 155 And R is 156 Identical or different, represents H, ammonium, an alkali metal, an alkyl group with or without a fluorine atom, an aryl group, or a sulfonyl group).
In the present invention, the term "perfluorinated organic group" refers to an organic group in which all hydrogen atoms bonded to carbon atoms are replaced with fluorine atoms. The perfluorinated organic group may have ether oxygen.
As the fluorine-containing monomer represented by the general formula (110), rf can be mentioned 111 Is C1-to-W10. The number of carbon atoms of the perfluoroalkyl group is preferably 1 to 5.
Examples of the perfluoroorganic group in the general formula (110) include a perfluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluorobutyl group, a perfluoropentyl group, and a perfluorohexyl group.
As the fluorine-containing monomer represented by the general formula (110), rf in the above general formula (110) can be further mentioned 111 Is a perfluoro (alkoxyalkyl) monomer having 4 to 9 carbon atoms, rf 111 Is of the formula:
[ chemical 9]
(wherein m represents 0 or an integer of 1 to 4), and Rf is represented by the following formula:
CF 3 CF 2 CF 2 -(O-CF(CF 3 )-CF 2 ) n -
(wherein n represents an integer of 1 to 4), and the like.
As the fluoromonomer represented by the general formula (110), preferred is
General formula (160): CF (compact flash) 2 ＝CF-ORf 161
(wherein Rf 161 A perfluoroalkyl group having 1 to 10 carbon atoms). Rf (radio frequency identification) 161 Preferably a perfluoroalkyl group having 1 to 5 carbon atoms.
The perfluoro (alkyl vinyl ether) is preferably at least 1 selected from the group consisting of fluoromonomers represented by the general formulae (160), (130) and (140).
The fluorine-containing monomer represented by the general formula (160) is preferably at least 1 selected from the group consisting of perfluoro (methyl vinyl ether), perfluoro (ethyl vinyl ether) and perfluoro (propyl vinyl ether), more preferably at least 1 selected from the group consisting of perfluoro (methyl vinyl ether) and perfluoro (propyl vinyl ether), and still more preferably perfluoro (methyl vinyl ether).
As the fluorine-containing monomer represented by the general formula (130), preferred isSelected from CF 2 ＝CFOCF 2 OCF 3 、CF 2 ＝CFOCF 2 OCF 2 CF 3 And CF (compact F) 2 ＝CFOCF 2 OCF 2 CF 2 OCF 3 At least 1 of the group consisting of.
The fluorine-containing monomer represented by the general formula (140) is preferably selected from CF 2 ＝CFOCF 2 CF(CF 3 )O(CF 2 ) 3 F、CF 2 ＝CFO(CF 2 CF(CF 3 )O) 2 (CF 2 ) 3 F and CF 2 ＝CFO(CF 2 CF(CF 3 )O) 2 (CF 2 ) 2 F, at least 1 of the group consisting of F.
As the fluorine-containing monomer represented by the general formula (150), it is preferably selected from CF 2 ＝CFOCF 2 CF 2 SO 2 F、CF 2 ＝CFOCF 2 CF(CF 3 )OCF 2 CF 2 SO 2 F、CF 2 ＝CFOCF 2 CF(CF 2 CF 2 SO 2 F)OCF 2 CF 2 SO 2 F and CF 2 ＝CFOCF 2 CF(SO 2 F) 2 At least 1 of the group consisting of.
Examples of perfluoro (alkyl allyl ether) include
General formula (180): CF (compact flash) 2 ＝CF-CF 2 -ORf 111
(wherein Rf 111 Represents a perfluorinated organic group).
Rf of the general formula (180) 111 Rf of the general formula (110) 111 The same applies. As Rf 111 A perfluoroalkyl group having 1 to 10 carbon atoms or a perfluoroalkoxyalkyl group having 1 to 10 carbon atoms is preferable. As the perfluoro (alkyl allyl ether) represented by the general formula (180), it is preferably selected from CF 2 ＝CF-CF 2 -O-CF 3 、CF 2 ＝CF-CF 2 -O-C 2 F 5 、CF 2 ＝CF-CF 2 -O-C 3 F 7 And CF (compact F) 2 ＝CF-CF 2 -O-C 4 F 9 At least 1 selected from the group consisting of CF, more preferably 2 ＝CF-CF 2 -O-C 2 F 5 、CF 2 ＝CF-CF 2 -O-C 3 F 7 And CF (compact F) 2 ＝CF-CF 2 -O-C 4 F 9 At least 1 of the group consisting of CF is further preferred 2 ＝CF-CF 2 -O-CF 2 CF 2 CF 3 。
The partially fluorinated monomer may be polymerized with the perfluorinated monomer. As partially fluorinated monomers, preference is given to having at least 1 double bond. As partially fluorinated monomers, preference is given to monomers selected from the group consisting of chlorotrifluoroethylene [ CTFE]Vinyl fluoride, vinylidene fluoride [ VDF ]]Trifluoroethylene, fluoroalkyl vinyl ether, fluoroalkyl ethylene, fluoroalkyl allyl ether, trifluoropropene, pentafluoropropene, trifluorobutene, tetrafluoroisobutene, hexafluoroisobutene, general formula (100): CHX (CHX) 101 ＝CX 102 Rf 101 (wherein X is 101 And X 102 One of them is H, the other is F, rf 101 Is a linear or branched fluoroalkyl group having 1 to 12 carbon atoms), a fluoromonomer, a fluorovinyl heterocyclic body, and a crosslinking site-providing monomer.
Examples of the fluoroalkyl vinyl ether include
General formula (120): CF (compact flash) 2 ＝CF-OCH 2 -Rf 121
(wherein Rf 121 A perfluoroalkyl group having 1 to 5 carbon atoms).
As the fluorine-containing monomer represented by the general formula (100), rf is preferable 101 Fluoromonomers which are linear fluoroalkyl groups, more preferably Rf 101 Fluorine-containing monomers that are linear perfluoroalkyl groups. Rf (radio frequency identification) 101 The number of carbon atoms of (2) is preferably 1 to 6. As the fluorine-containing monomer represented by the general formula (100), CH can be mentioned 2 ＝CFCF 3 、CH 2 ＝CFCF 2 CF 3 、CH 2 ＝CFCF 2 CF 2 CF 3 、CH 2 ＝CFCF 2 CF 2 CF 2 H、CH 2 ＝CFCF 2 CF 2 CF 2 CF 3 、CHF＝CHCF 3 (E-body), chf=chcf 3 (Z body) and the like, whereinPreferably CH 2 ＝CFCF 3 2, 3-tetrafluoropropene is shown.
As the fluoroalkyl ethylene, preferred is
General formula (170): CH (CH) 2 ＝CH-(CF 2 ) n -X 171
(wherein X is 171 Is H or F, n is an integer of 3 to 10), more preferably selected from the group consisting of CH 2 ＝CH-C 4 F 9 CH (CH) 2 ＝CH-C 6 F 13 At least 1 of the group consisting of.
The fluorovinyl heterocyclic compound may be represented by the general formula (230):
[ chemical 10]
(wherein X is 231 And X 232 Is independently F, cl, methoxy or fluoromethoxy, Y 231 Is Y 232 Or Y 233 。
[ chemical 11]
-FC＝CF-(Y 232 )
(wherein Z is 231 And Z 232 Independently F or a fluoroalkyl group having 1 to 3 carbon atoms).
As the monomer providing a crosslinking site, at least 1 selected from the group consisting of:
general formula (181): CX (CX) 181 2 ＝CX 182 -R f 181 CHR 181 X 183
(wherein X is 181 And X 182 Independently a hydrogen atom, a fluorine atom or CH 3 ，R f 181 Is a fluoroalkylene group, a perfluoroalkylene group, a fluoro (poly) oxyalkylene groupRadical or perfluoro (poly) oxyalkylene, R 181 Is a hydrogen atom or CH 3 ，X 183 An iodine atom or a bromine atom), a fluorine-containing monomer represented by,
General formula (190): CX (CX) 191 2 ＝CX 192 -R f 191 X 193
(wherein X is 191 And X 192 Independently a hydrogen atom, a fluorine atom or CH 3 ，R f 191 Is a fluoroalkylene, perfluoroalkylene, fluoropolyoxyalkylene or perfluor polyoxyalkylene group, X 193 An iodine atom or a bromine atom), a fluorine-containing monomer represented by,
General formula (200): CF (compact flash) 2 ＝CFO(CF 2 CF(CF 3 )O) m (CF 2 ) n -X 201
(wherein m is an integer of 0 to 5, n is an integer of 1 to 3, X 201 Is cyano, carboxyl, alkoxycarbonyl, iodine atom, bromine atom or-CH 2 I) The fluoromonomer shown, and
general formula (210): CH (CH) 2 ＝CFCF 2 O(CF(CF 3 )CF 2 O) m (CF(CF 3 )) n -X 211
(wherein m is an integer of 0 to 5, n is an integer of 1 to 3, X 211 Is cyano, carboxyl, alkoxycarbonyl, iodine atom, bromine atom or-CH 2 OH) fluorine-containing monomer
General formula (220): CR (computed radiography) 221 R 222 ＝CR 223 -Z 221 -CR 224 ＝CR 225 R 226
(wherein R is 221 、R 222 、R 223 、R 224 、R 225 And R is 226 The same or different are hydrogen atoms or alkyl groups with 1 to 5 carbon atoms. Z is Z 221 Straight-chain or branched alkylene having 1 to 18 carbon atoms, cycloalkylene having 3 to 18 carbon atoms, at least partially fluorinated alkylene or oxyalkylene having 1 to 10 carbon atoms, or
-(Q) p -CF 2 O-(CF 2 CF 2 O) m (CF 2 O) n -CF 2 -(Q) p -
(wherein Q is an alkylene group or an oxyalkylene group, p is 0 or 1.m/n is 0.2 to 5), and a (per) fluoropolyoxyalkylene group having a molecular weight of 500 to 10000.
X 183 And X 193 Iodine atoms are preferred. R is R f 181 And R is f 191 A perfluoroalkylene group having 1 to 5 carbon atoms is preferable. R is R 181 Preferably a hydrogen atom. X is X 201 Preferably cyano, alkoxycarbonyl, iodine, bromine or-CH 2 I。X 211 Preferably cyano, alkoxycarbonyl, iodine, bromine or-CH 2 OH。
As monomers providing crosslinking sites, monomers selected from the group consisting of CF are preferred 2 ＝CFOCF 2 CF(CF 3 )OCF 2 CF 2 CN、CF 2 ＝CFOCF 2 CF(CF 3 )OCF 2 CF 2 COOH、CF 2 ＝CFOCF 2 CF(CF 3 )OCF 2 CF 2 CH 2 I、CF 2 ＝CFOCF 2 CF 2 CH 2 I、CH 2 ＝CFCF 2 OCF(CF 3 )CF 2 OCF(CF 3 )CN、CH 2 ＝CFCF 2 OCF(CF 3 )CF 2 OCF(CF 3 )COOH、CH 2 ＝CFCF 2 OCF(CF 3 )CF 2 OCF(CF 3 )CH 2 OH、CH 2 ＝CHCF 2 CF 2 I、CH 2 ＝CH(CF 2 ) 2 CH＝CH 2 、CH 2 ＝CH(CF 2 ) 6 CH＝CH 2 And CF (compact F) 2 ＝CFO(CF 2 ) 5 At least 1 of CN, more preferably selected from CF 2 ＝CFOCF 2 CF(CF 3 )OCF 2 CF 2 CN and CF 2 ＝CFOCF 2 CF 2 CH 2 At least 1 of the group consisting of I.
In the above polymerization, the above perfluorinated monomer may be polymerized with a non-fluorinated monomer. Examples of the non-fluorinated monomer include hydrocarbon monomers reactive with the fluorinated monomer. Examples of the hydrocarbon monomer include: olefins such as ethylene, propylene, butene, and isobutene; alkyl vinyl ethers such as ethyl vinyl ether, propyl vinyl ether, butyl vinyl ether, isobutyl vinyl ether and cyclohexyl vinyl ether; vinyl esters such as vinyl acetate, vinyl propionate, vinyl n-butyrate, vinyl isobutyrate, vinyl valerate, vinyl pivalate, vinyl caproate, vinyl caprylate, vinyl caprate, vinyl versatate, vinyl laurate, vinyl myristate, vinyl palmitate, vinyl stearate, vinyl benzoate, vinyl p-tert-butylbenzoate, vinyl cyclohexane carboxylate, vinyl monochloroacetate, vinyl adipate, vinyl acrylate, vinyl methacrylate, vinyl crotonate, vinyl sorbate, vinyl cinnamate, vinyl undecylenate, vinyl glycolate, vinyl hydroxypropionate, vinyl hydroxybutyrate, vinyl hydroxyvalerate, vinyl hydroxyisobutyrate, vinyl hydroxycyclohexane carboxylate; alkyl allyl ethers such as ethyl allyl ether, propyl allyl ether, butyl allyl ether, isobutyl allyl ether, and cyclohexyl allyl ether; alkyl allyl esters such as ethyl allyl ester, propyl allyl ester, butyl allyl ester, isobutyl allyl ester, and cyclohexyl allyl ester; (meth) acrylic esters such as methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, butyl acrylate, butyl methacrylate, hexyl methacrylate, cyclohexyl methacrylate, and vinyl methacrylate; etc.
The non-fluorine-containing monomer may be a hydrocarbon monomer having a functional group (excluding a monomer providing a crosslinking site). Examples of the functional group-containing hydrocarbon monomer include: hydroxyalkyl vinyl ethers such as hydroxyethyl vinyl ether, hydroxypropyl vinyl ether, hydroxybutyl vinyl ether, hydroxyisobutyl vinyl ether and hydroxycyclohexyl vinyl ether; non-fluorinated monomers having a carboxyl group such as acrylic acid, methacrylic acid, itaconic acid, succinic anhydride, fumaric acid, fumaric anhydride, crotonic acid, maleic anhydride, and perfluorobutenoic acid; non-fluorine-containing monomers having a sulfo group such as vinylsulfonic acid; glycidyl group-containing non-fluorine-containing monomers such as glycidyl vinyl ether and glycidyl allyl ether; amino group-containing non-fluorine-containing monomers such as aminoalkyl vinyl ether and aminoalkyl allyl ether; non-fluorine-containing monomers having an amide group such as (meth) acrylamide and methylolacrylamide; non-fluorine-containing monomers having a nitrile group such as acrylonitrile and methacrylonitrile; etc.
In the above polymerization, 1 or 2 or more monomers such as a perfluoro monomer are polymerized to obtain desired particles of the fluoropolymer.
The amount of the polymer (1) to be added in the polymerization is preferably more than 0.0001% by mass and 20% by mass or less, more preferably 0.001% by mass or more, still more preferably 10% by mass or less, and still more preferably 5% by mass or less, relative to the aqueous medium. By setting the amount of the polymer (1) to be added within the above range, polymerization of the perfluoromonomer in the aqueous medium can be smoothly performed. The amount of the polymer (1) added is the total amount of the polymer (1) added during the polymerization.
In the above polymerization, the polymer (1) may be added at one time, or the polymer (1) may be added continuously. The continuous addition of the polymer (1) means, for example, that the polymer (1) is not added at once but is added over time and without interruption or in batches. In the above polymerization, an aqueous solution containing the polymer (1) and water may be prepared and added.
In the above polymerization, at least 1 polymer (1) may be used, and a fluoropolymer can be efficiently produced. In addition, 2 or more compounds contained in the polymer (1) may be used simultaneously, and any compound having a surface activity other than the polymer (1) may be used simultaneously as long as the compound is volatile or may remain in a molded article or the like made of a fluorine-containing polymer.
In the above polymerization, a nucleating agent may be used. The addition amount of the nucleating agent may be appropriately selected according to the kind of the nucleating agent. The amount of the nucleating agent to be added may be 5000 mass ppm or less, preferably 1000 mass ppm or less, more preferably 500 mass ppm or less, still more preferably 100p mass ppm or less, particularly preferably 50 mass ppm or less, and most preferably 10 mass ppm or less, with respect to the aqueous medium.
In the above polymerization, the nucleating agent is preferably added to the aqueous medium before the start of the polymerization or before the solid content of the fluoropolymer formed in the aqueous medium reaches 5.0 mass%. By adding the nucleating agent at the initial stage of polymerization, an aqueous dispersion having a small average primary particle diameter and excellent stability can be obtained.
The amount of the nucleating agent added at the initial stage of polymerization is preferably 0.001 mass% or more, more preferably 0.01 mass% or more, still more preferably 0.05 mass% or more, and particularly preferably 0.1 mass% or more, based on the fluoropolymer obtained. The upper limit of the amount of the nucleating agent to be added at the initial stage of polymerization is not limited, and is, for example, 2000 mass%.
By using a nucleating agent, a fluoropolymer having a smaller primary particle size can be obtained as compared to a polymerization carried out in the absence of the above-described nucleating agent.
Examples of the nucleating agent include dicarboxylic acid, perfluoropolyether (PFPE) acid or a salt thereof, and hydrocarbon-containing surfactant. The nucleating agent preferably does not contain an aromatic ring, and is preferably an aliphatic compound.
The nucleating agent is preferably added before or simultaneously with the addition of the polymerization initiator, and the particle size distribution can be adjusted by adding the nucleating agent during the polymerization.
The preferable amount of the dicarboxylic acid is 1000 mass ppm or less, more preferably 500 mass ppm or less, and still more preferably 100 mass ppm or less relative to the aqueous medium.
The perfluoropolyether (PFPE) acid or a salt thereof may have any chain structure in which oxygen atoms in the main chain of the molecule are separated by a saturated fluorocarbon group having 1 to 3 carbon atoms. In addition, 2 or more fluorocarbon groups may be present in the molecule. Representative structures have repeating units represented by the following formula.
(-CFCF 3 -CF 2 -O-) n (VII)
(-CF 2 -CF 2 -CF 2 -O-) n (VIII)
(-CF 2 -CF 2 -O-) n -(-CF 2 -O-) m (IX)
(-CF 2 -CFCF 3 -O-)n-(-CF 2 -O-) m (X)
These structures are described by Kasai in J.Appl.Polymer Sci.57,797 (1995). As disclosed in this document, the above PFPE acid or a salt thereof may have a carboxylic acid group or a salt thereof at one or both ends. In addition, the above PFPE acid or a salt thereof may have a sulfonic acid group, a phosphonic acid group or a salt thereof at one end or both ends. In addition, the above PFPE acid or a salt thereof may have different groups at each end. With monofunctional PFPEs, the other end of the molecule is typically perfluorinated and may also contain hydrogen or chlorine atoms. The above-mentioned PFPE acid or a salt thereof has at least 2 ether oxygens, preferably has at least 4 ether oxygens, and even more preferably has at least 6 ether oxygens. Preferably at least one, more preferably at least two of such fluorocarbon groups, spaced apart by ether oxygen, have 2 or 3 carbon atoms. Even more preferably at least 50% of the fluorocarbon groups separating the ether oxygen have 2 or 3 carbon atoms. In addition, the PFPE acid or salt thereof preferably has at least 15 carbon atoms in total, for example, a preferred minimum value of n or n+m in the repeating unit structure is at least 5. More than 2 kinds of the above PFPE acids having an acid group at one end or both ends or salts thereof can be used in the production method of the present invention. The above-mentioned PFPE acid or salt thereof preferably has a number average molecular weight of less than 6000 g/mol.
The amount of the hydrocarbon-containing surfactant to be added is preferably 40 mass ppm or less, more preferably 30 mass ppm or less, and still more preferably 20 mass ppm or less, relative to the aqueous medium. It is presumed that the amount of ppm of the lipophilic nucleation site present in the aqueous medium is less than the amount added. Therefore, the amount of the lipophilic nucleation site is less than 40 mass ppm, 30 mass ppm, and 20 mass ppm, respectively. The lipophilic nucleation sites are thought to exist as molecules, and therefore, even a very small amount of the hydrocarbon-containing surfactant can generate a large amount of lipophilic nucleation sites. Therefore, even if only about 1 mass ppm of the above-mentioned hydrocarbon-containing surfactant is added to the aqueous medium, a beneficial effect can be obtained. The lower limit is preferably 0.01 mass ppm.
The hydrocarbon-containing surfactant includes silicone surfactants such as those disclosed in U.S. Pat. No. 7897682 (Brothers et al) and U.S. Pat. No. 7977438 (Brothers et al), and includes nonionic surfactants and cationic surfactants.
As the hydrocarbon-containing surfactant, a nonionic surfactant (for example, nonionic hydrocarbon surfactant) is preferable. That is, as the nucleating agent, a nonionic surfactant is preferable.
(nonionic surfactant)
The nonionic surfactant used in the production method of the present invention generally contains no charged groups and has a hydrophobic portion as a long-chain hydrocarbon. The hydrophilic portion of the nonionic surfactant contains water-soluble functional groups such as chains of vinyl ethers derived from polymerization with ethylene oxide.
The nonionic surfactant may be the following.
Polyoxyethylene alkyl ethers, polyoxyethylene alkylphenyl ethers, polyoxyethylene alkyl esters, sorbitan alkyl esters, polyoxyethylene sorbitan alkyl esters, glycerides, and derivatives thereof.
Specific examples of polyoxyethylene alkyl ethers: polyoxyethylene lauryl ether, polyoxyethylene cetyl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, polyoxyethylene behenyl ether, and the like.
Specific examples of polyoxyethylene alkylphenyl ethers: polyoxyethylene nonylphenyl ether, polyoxyethylene octylphenyl ether, and the like.
Specific examples of polyoxyethylene alkyl esters: polyethylene glycol monolaurate, polyethylene glycol monooleate, polyethylene glycol monostearate, and the like.
Specific examples of sorbitan alkyl esters: polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan monooleate, and the like.
Specific examples of polyoxyethylene sorbitan alkyl esters: polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate, and the like.
Specific examples of glycerides are: glycerol mono-tetradecanoate, glycerol monostearate, glycerol monooleate, and the like.
Specific examples of the above derivatives are: polyoxyethylene alkylamines, polyoxyethylene alkylphenyl-formaldehyde condensates, polyoxyethylene alkyl ether phosphates, and the like.
The ethers and esters may have an HLB value of from 10 to 18.
Examples of the nonionic surfactant include Triton (registered trademark) X series (X15, X45, X100, etc.), tergitol (registered trademark) 15-S series, tergitol (registered trademark) TMN series (TMN-6, TMN-10, TMN-100, etc.), tergitol (registered trademark) L series, pluronic (registered trademark) R series (31R 1, 17R2, 10R5, 25R4 (m-22, n-23), iconol (registered trademark) TDA series (TDA-6, TDA-9, TDA-10, etc.) manufactured by BASF.
The nonionic surfactant is preferably a fluorine-free nonionic surfactant. Examples thereof include: ether nonionic surfactants such as polyoxyethylene alkylphenyl ether, polyoxyethylene alkyl ether, and polyoxyethylene alkylene alkyl ether; polyoxyethylene derivatives such as ethylene oxide/propylene oxide block copolymers; sorbitan fatty acid esters, polyoxyethylene sorbitol fatty acid esters, glycerin fatty acid esters, polyoxyethylene fatty acid esters and other ester nonionic surfactants; amine nonionic surfactants such as polyoxyethylene alkylamine and alkyl alkanolamide; etc.
In the nonionic surfactant described above, the hydrophobic group thereof may be any one of alkylphenol groups, linear alkyl groups and branched alkyl groups.
As the nonionic surfactant, a nonionic surfactant represented by the general formula (i) is preferable.
R 6 -O-A 1 -H (i)
(wherein R is 6 Is a linear or branched primary or secondary alkyl group having 8 to 18 carbon atoms, A 1 Is a polyoxyalkylene chain. )
In the general formula (i), R 6 The number of carbon atoms of (2) is preferably 10 to 16, more preferably 12 to 16. If R is 6 When the number of carbon atoms is 18 or less, excellent sedimentation stability of the composition can be easily obtained. In addition, if R 6 If the number of carbon atoms exceeds 18, the flow temperature is high, and therefore, handling is difficult. If R is 6 If the number of carbon atoms is less than 8, the surface tension of the composition increases, and the permeability or wettability tends to decrease.
A 1 The polyoxyalkylene chain of (a) may be composed of ethylene oxide and propylene oxide. Is a polyoxyalkylene chain having an average repetition number of an oxyethylene group of 5 to 20 and an average repetition number of an oxypropylene group of 0 to 2, and is a hydrophilic group. The number of ethylene oxide units may comprise any of the broad or narrow unimodal distributions typically provided, or the broader or bimodal distributions obtained by blending. When the average number of repetitions of the oxypropylene group exceeds 0, the oxyethylene group and oxypropylene group in the polyoxyalkylene chain may be arranged in a block form or may be arranged in a random form. From the viewpoints of viscosity and sedimentation stability of the composition, a polyoxyalkylene chain composed of an average repetition number of oxyethylene groups of 7 to 12 and an average repetition number of oxypropylene groups of 0 to 2 is preferable. In particular, if A 1 An average oxypropylene group of 0.5 to 1.5 is preferable because low foamability is good.
More preferably R 6 Is (R ') (R') HC-, where R 'and R' are identical or different linear, branched or cyclic alkyl radicals, the total number of carbon atoms being at least 5, preferably from 7 to 17. Preferably at least one of R 'or R' is a branched or cyclic hydrocarbon group.
Specific examples of the polyoxyethylene alkyl ether include C 13 H 27 -O-(C 2 H 4 O) n -H、C 12 H 25 -O-(C 2 H 4 O) n -H、C 10 H 21 CH(CH 3 )CH 2 -O-(C 2 H 4 O) n -H、C 13 H 27 -O-(C 2 H 4 O) n -(CH(CH 3 )CH 2 O)-H、C 16 H 33 -O-(C 2 H 4 O) n -H、HC(C 5 H 11 )(C 7 H 15 )-O-(C 2 H 4 O) n H (in the formulae, n is an integer of 1 or more), and the like. Examples of the commercial products of the polyoxyethylene alkyl ether include Genapol X series (manufactured by Clariant corporation) such as Genapol X080 (trade name), noigen TDS series (manufactured by first Industrial pharmaceutical Co., ltd.) such as Noigen TDS-80 (trade name), leocol TD series (manufactured by LION Co., ltd.) such as Leocol TD-90 (trade name), LIONOL TD series (manufactured by LION Co., ltd.), T-Det A series (manufactured by Harcros Chemicals Co., ltd.) such as T-Det A138 (trade name), tergitol (registered trade name) 15-S series (manufactured by Dow chemical Co., ltd.).
The nonionic surfactant is also preferably an ethoxylate of 2,6, 8-trimethyl-4-nonanol having an average of about 4 to about 18 ethylene oxide units, an ethoxylate of 2,6, 8-trimethyl-4-nonanol having an average of about 6 to about 12 ethylene oxide units, or mixtures thereof. Nonionic surfactants of this type are also commercially available, for example, as TERGITOL TMN-6, TERGITOL TMN-10, and TERGITOL TMN-100X (both manufactured by Dow chemical Co.).
In addition, the hydrophobic group of the nonionic surfactant may be any one of alkylphenol group, linear alkyl group and branched alkyl group. For example, the nonionic surfactant may be represented by the general formula (ii)
R 7 -C 6 H 4 -O-A 2 -H(ii)
(wherein R is 7 Is a linear or branched alkyl group having 4 to 12 carbon atoms, A 2 Is a polyoxyalkylene chain). Specific examples of the nonionic surfactant include Triton (registered trademark) X-100 (trade name, manufactured by Dow chemical Co., ltd.).
A 2 The polyoxyalkylene chain of (a) may be composed of ethylene oxide and propylene oxide. Is a polyoxyalkylene chain having an average repetition number of an oxyethylene group of 5 to 20 and an average repetition number of an oxypropylene group of 0 to 2, and is a hydrophilic group. The number of ethylene oxide units may comprise any of the broad or narrow unimodal distributions typically provided, or the broader or bimodal distributions obtained by blending. When the average number of repetitions of the oxypropylene group exceeds 0, the oxyethylene group and oxypropylene group in the polyoxyalkylene chain may be arranged in a block form or may be arranged in a random form. From the viewpoints of viscosity and sedimentation stability of the composition, a polyoxyalkylene chain composed of an average repetition number of oxyethylene groups of 7 to 12 and an average repetition number of oxypropylene groups of 0 to 2 is preferable. In particular, if A 2 An average oxypropylene group of 0.5 to 1.5 is preferable because low foamability is good.
More preferably, R 7 Is a primary or secondary alkyl group, more preferably (R ') (R') HC-, where R 'and R' are identical or different linear, branched or cyclic alkyl groups, the total number of carbon atoms being at least 5, preferably from 7 to 17. Preferably at least one of R 'or R' is a branched or cyclic hydrocarbon group.
The nonionic surfactant may be a polyol compound. Specifically, a polyol compound described in international publication No. 2011/014715 and the like are exemplified. Typical examples of the polyol compound include a compound having 1 or more sugar units as polyol units. The saccharide units may be modified to contain at least 1 long chain. Examples of suitable polyol compounds containing at least 1 long chain moiety include alkyl glycosides, modified alkyl glycosides, sugar esters and combinations thereof. Examples of the sugar include, but are not limited to, monosaccharides, oligosaccharides, and sorbitan. Examples of monosaccharides include five-carbon sugars and six-carbon sugars. Typical examples of monosaccharides include ribose, glucose, galactose, mannose, fructose, arabinose, and xylose. The oligosaccharide may be an oligomer of 2 to 10 monosaccharides which may be the same or different. Examples of the oligosaccharide include sucrose, maltose, lactose, raffinose and isomaltose, but are not limited thereto.
Typically, as a sugar suitable for the polyol compound, there may be mentioned a five-membered ring compound having 4 carbon atoms and 1 hetero atom (typically oxygen or sulfur, preferably oxygen atom), or a six-membered ring compound having 5 carbon atoms and the above 1 hetero atom, preferably oxygen atom. They further contain at least 2 or at least 3 hydroxyl groups (-OH groups) bonded to a carbon ring atom. Typically, to make ether or ester linkages between the long chain residue and the sugar moiety, the sugar is modified in the following ways: more than 1 of the hydrogen atoms of the hydroxyl (and/or hydroxyalkyl) groups bonded to the carbon ring atoms are replaced by long chain residues. The sugar polyol may contain 1 sugar unit or 2 or more sugar units. 1 saccharide unit or more than 2 saccharide units may be modified with the long chain moiety described above. Specific examples of the sugar polyol compound include glycosides, sugar esters, sorbitan esters, and mixtures and combinations thereof.
The preferred class of polyol compounds is alkyl or modified alkyl glucosides. These classes of surfactants contain at least 1 glucose moiety. There may be mentioned
[ chemical 12]
(wherein x represents 0, 1, 2, 3, 4, or 5, R 1 And R is 2 Independently represents H or a long chain unit containing at least 6 carbon atoms, wherein R 1 And R is 2 At least 1 of which is not H). As R 1 And R is 2 Typical examples of (a) include aliphatic alcohol residues. Examples of the aliphatic alcohol include hexanol, heptanol, octanol, nonanol, decanol, undecanol, dodecanol (lauryl alcohol), tetradecanol, hexadecanol (cetyl alcohol), heptadecanol, octadecanol (stearyl alcohol), eicosanoic acid, and combinations thereof. The above formula shows a specific example of an alkylpolyglucoside that represents glucopyranose form, butIt will be appreciated that other sugars or sugars that are the same sugar but in different enantiomeric or diastereomeric forms may also be used.
The alkyl glucosides can be obtained, for example, by acid-catalyzed reaction of glucose, starch, or n-butyl glucoside with aliphatic alcohols, in typical examples, whereby mixtures of the various alkyl glucosides are obtained (Alkylpolygycoside, rompp, lexikon Chemie, version 2.0, stuttgart/New York, georg Thieme Verlag, 1999). Examples of the aliphatic alcohol include hexanol, heptanol, octanol, nonanol, decanol, undecanol, dodecanol (lauryl alcohol), tetradecanol, hexadecanol (cetyl alcohol), heptadecanol, octadecanol (stearyl alcohol), eicosanoic acid, and combinations thereof. Alkyl glucosides are commercially available under the trade names GLUCOPON or DISPONIL from Dulborof Cognis GmbH, germany.
Examples of the other nonionic surfactant include difunctional block copolymers supplied from BASF as Pluronic (registered trademark) R series and tridecyl alcohol alkoxylates supplied from BASF as Iconol (registered trademark) TDA series.
The nonionic surfactant is preferably at least 1 selected from the group consisting of a nonionic surfactant represented by the general formula (i) and a nonionic surfactant represented by the general formula (ii), and more preferably a nonionic surfactant represented by the general formula (i).
The nonionic surfactant preferably does not contain an aromatic moiety.
In the above polymerization, a compound having a functional group and a hydrophilic group capable of reacting by radical polymerization can be used together with the polymer (1). As the compound having a functional group and a hydrophilic group capable of reacting by radical polymerization, the same compound as the modified monomer (a) described later can be used.
In the above polymerization, additives for stabilizing the respective compounds may be used in addition to the polymer (1) and other compounds having surface active properties according to the intended use. Examples of the additives include buffers, pH adjusters, stabilization aids, and dispersion stabilizers.
As the stabilizing aid, paraffin wax, fluorine-based oil, fluorine-based solvent, silicone oil, and the like are preferable. The stabilizing aids may be used singly or in combination of 1 or more than 2. As the stabilizing aid, paraffin is more preferable. The paraffin wax may be liquid, semi-solid or solid at room temperature, but is preferably a saturated hydrocarbon having 12 or more carbon atoms. The melting point of paraffin wax is usually preferably 40 to 65 ℃, more preferably 50 to 65 ℃.
The amount of the stabilizing additive to be used is preferably 0.1 to 12% by mass, more preferably 0.1 to 8% by mass, based on the mass of the aqueous medium to be used. The stabilizing agent is preferably sufficiently hydrophobic and is completely separated from the aqueous dispersion after polymerization, and is not a contaminating component.
The polymerization may be performed as follows: the polymerization can be carried out by charging an aqueous medium, the above polymer (1), a monomer and other additives as needed into a polymerization reactor, stirring the contents of the reactor, maintaining the reactor at a predetermined polymerization temperature, and then adding a predetermined amount of a polymerization initiator to initiate the polymerization. After the polymerization reaction is started, a monomer, a polymerization initiator, a chain transfer agent, the polymer (1), and the like may be additionally added according to the purpose. The polymer (1) may be added after the start of the polymerization reaction.
In general, the polymerization temperature is 5℃to 120℃and the polymerization pressure is 0.05MPaG to 10MPaG. The polymerization temperature and polymerization pressure are appropriately determined depending on the kind of the monomer used, the molecular weight of the objective fluoropolymer, and the reaction rate.
The polymerization initiator is not particularly limited as long as it can generate radicals in the polymerization temperature range, and known oil-soluble and/or water-soluble polymerization initiators can be used. Further, the polymerization may be initiated in a redox form in combination with a reducing agent or the like. The concentration of the polymerization initiator is appropriately determined according to the kind of the monomer, the molecular weight of the target fluoropolymer, and the reaction rate.
As the polymerization initiator, an oil-soluble radical polymerization initiator, a water-soluble radical polymerization initiator, or an azo compound can be used.
The oil-soluble radical polymerization initiator may be a known oil-soluble peroxide, and the following peroxides are exemplified as typical examples: dialkyl peroxycarbonates such as diisopropyl peroxydicarbonate and di-sec-butyl peroxydicarbonate; peroxyesters such as t-butyl peroxyisobutyrate and t-butyl peroxypivalate; dialkyl peroxides such as di-t-butyl peroxide; di (ω -hydro-dodecafluorohexanoyl) peroxide, di (ω -hydro-tetradecahaloyl) peroxide, di (ω -hydro-hexadecanoyl) peroxide, di (perfluorobutanoyl) peroxide, di (perfluoropentanoyl) peroxide, di (perfluorohexanoyl) peroxide, di (perfluoroheptanoyl) peroxide, di (perfluorooctanoyl) peroxide, di (perfluorononanoyl) peroxide, di (ω -chloro-hexafluorobutanoyl) peroxide, di (ω -chloro-decafluorohexanoyl) peroxide, di (ω -chloro-tetradecanoyl) peroxide, ω -hydro-dodecafluoroheptanoyl- ω -hexadecanoyl-peroxide, ω -chloro-hexafluorobutanoyl- ω -chloro-decafluorodecanoyl-peroxide, ω -hydrododecafluoroheptanoyl-perfluoroheptanoyl-peroxide, di (dichloro-penta-fluoropentanoyl) peroxide, di (trichlorooctahexanoyl) peroxide, di (tetrafluoroundecanoyl) peroxide, di (ω -chloro-dodecafluorodecanoyl) peroxide, di (dichloro-dodecanoyl) or di (fluoro-dodecanoyl) such as di (ω -chloro-dodecafluoroheptanoyl) peroxide; etc.
The water-soluble radical polymerization initiator may be a known water-soluble peroxide, and examples thereof include ammonium salts such as persulfuric acid, perboric acid, perchloric acid, perphosphoric acid, and percarbonic acid, organic peroxides such as potassium salt, sodium salt, disuccinic acid peroxide, and dipentaerythritol peroxide, t-butyl peroxymaleate, and t-butyl hydroperoxide. The composition may contain a reducing agent such as a sulfite at a ratio of 0.1 to 20 times that of the peroxide.
For example, in the case of performing polymerization at a low temperature of 30 ℃ or lower, a redox initiator obtained by combining an oxidizing agent and a reducing agent is preferably used as the polymerization initiator. Examples of the oxidizing agent include persulfates, organic peroxides, potassium permanganate, manganese triacetate, and ammonium cerium nitrate. Examples of the reducing agent include sulfite, bisulfite, bromate, diimine, and oxalic acid. Examples of the persulfate include ammonium persulfate, potassium persulfate, and sodium persulfate. The sulfite may be sodium sulfite or ammonium sulfite. In order to increase the decomposition rate of the initiator, it is also preferable to add a copper salt or an iron salt to the combination of redox initiators. Copper salts include copper (II) sulfate, and iron salts Include Iron (II) sulfate.
Examples of the redox initiator include potassium permanganate/oxalic acid, ammonium persulfate/bisulfite/ferric sulfate, manganese triacetate/oxalic acid, ceric ammonium nitrate/oxalic acid, bromate/bisulfite, and the like, and potassium permanganate/oxalic acid is preferable. In the case of using a redox initiator, either one of the oxidizing agent and the reducing agent may be charged into the polymerization vessel in advance, and then the other may be continuously or intermittently added to initiate polymerization. For example, in the case of using potassium permanganate/oxalic acid, it is preferable to charge oxalic acid into a polymerization vessel and continuously add potassium permanganate thereto.
The amount of the polymerization initiator to be added is not particularly limited, and may be at least an amount (for example, several ppm relative to the concentration of water) at one time, sequentially or continuously at the initial stage of polymerization, to such an extent that the polymerization rate does not significantly decrease. The upper limit is a range in which heat removal from the apparatus surface can be performed by using the polymerization reaction heat and the reaction temperature can be increased, and the upper limit is more preferably a range in which the polymerization reaction heat can be removed from the apparatus surface.
The aqueous medium is a reaction medium for conducting polymerization, and is a liquid containing water. The aqueous medium is not particularly limited as long as it contains water, and may contain water and a non-fluorinated organic solvent such as alcohol, ether, ketone, and/or a fluorinated organic solvent having a boiling point of 40 ℃ or less.
In the above polymerization, a known chain transfer agent, radical scavenger and decomposer may be further added according to the purpose to adjust the polymerization rate and molecular weight.
Examples of the chain transfer agent include esters such as dimethyl malonate, diethyl malonate, methyl acetate, ethyl acetate, butyl acetate, and dimethyl succinate, various halogenated hydrocarbons such as isopentane, methane, ethane, propane, methanol, isopropanol, acetone, various mercaptans, and carbon tetrachloride, and cyclohexane.
As the chain transfer agent, a bromine compound or an iodine compound can be used. Examples of the polymerization method using a bromine compound or an iodine compound include a method of polymerizing a fluorine-containing monomer in an aqueous medium in a substantially oxygen-free state in the presence of a bromine compound or an iodine compound (iodine transfer polymerization method). Typical examples of the bromine compound or iodine compound to be used include, for example, general formulae:
R a I x Br y
(wherein x and y are integers of 0 to 2 and satisfy 1.ltoreq.x+y.ltoreq.2, R a Is a saturated or unsaturated fluorocarbon group or chlorofluorocarbon group having 1 to 16 carbon atoms or a hydrocarbon group having 1 to 3 carbon atoms, wherein R is a With or without oxygen atoms). By using a bromine compound or iodine compound, iodine or bromine is introduced into the polymer, functioning as a crosslinking point.
Examples of the bromine compound or iodine compound include 1, 3-diiodoperfluoropropane, 2-iodoperfluoropropane, 1, 3-diiodo-2-chloroperfluoropropane, 1, 4-diiodoperfluorobutane, 1, 5-diiodo-2, 4-chloroperfluoropentane, 1, 6-diiodoperfluorohexane, 1, 8-diiodoperfluorooctane, 1, 12-diiodoperfluorododecane, 1, 16-diiodoperfluorohexadecane, diiodomethane, 1, 2-diiodoethane, 1, 3-diiodon-propane and CF 2 Br 2 、BrCF 2 CF 2 Br、CF 3 CFBrCF 2 Br、CFClBr 2 、BrCF 2 CFClBr、CFBrClCFClBr、BrCF 2 CF 2 CF 2 Br、BrCF 2 CFBrOCF 3 1-bromo-2-iodoperfluoroethane, 1-bromo-3-iodoperfluoropropane, 1-bromo-4-iodoperfluorobutane, 2-bromo-3-iodoperfluorobutane, 3-bromo-4-iodoperfluoro-1-butene, 2-bromo-4-iodoperfluoro-1-butene, monoiodo monobromide substituent of benzene, diiodomonobromide substituent, and (2-iodoethyl)Radical), and (2-bromoethyl) substituents, etc., which may be used alone or in combination with each other.
Among these, 1, 4-diiodoperfluorobutane, 1, 6-diiodoperfluorohexane and 2-iodoperfluoropropane are preferably used from the viewpoints of polymerization reactivity, crosslinking reactivity, availability and the like.
The amount of the chain transfer agent to be used is usually 1 to 50,000 mass ppm, preferably 1 to 20,000 mass ppm, based on the total amount of the fluoromonomer to be supplied.
The chain transfer agent may be added to the reaction vessel at one time before the start of polymerization, may be added at one time after the start of polymerization, may be added in several times during the polymerization, or may be added continuously during the polymerization.
As the polymerization initiator, organic peroxides such as persulfates (e.g., ammonium persulfate), disuccinic acid peroxide, and dipentaerythritol peroxide may be used alone or in the form of a mixture of these. Alternatively, the catalyst may be used in combination with a reducing agent such as sodium sulfite to prepare a redox system. Further, a radical scavenger such as hydroquinone or catechol, or a decomposition agent such as a peroxide such as ammonium sulfite may be added to adjust the radical concentration in the system during the polymerization.
In the above polymerization, the perfluoro monomer is polymerized in an aqueous medium in the presence of the polymer (1) to produce an aqueous dispersion of the fluoropolymer particles, and the perfluoro monomer is seed-polymerized into the fluoropolymer particles in the aqueous dispersion of the fluoropolymer particles to thereby obtain the fluoropolymer.
The above polymerization is preferably carried out in the substantial absence of a fluorosurfactant (excluding compounds having a functional group and a hydrophilic group capable of reacting by radical polymerization). Although a fluorosurfactant has been conventionally used in the polymerization of perfluoromonomers in an aqueous medium, according to the production method of the present invention, a fluoropolymer can be obtained even when a fluorosurfactant is not used.
In the present invention, the term "in the substantial absence of a fluorosurfactant" means that the amount of the fluorosurfactant relative to the aqueous medium is 10 mass ppm or less. The amount of the fluorosurfactant relative to the aqueous medium is preferably 1 ppm by mass or less, more preferably 100 ppb by mass or less, still more preferably 10 ppb by mass or less, and still more preferably 1 ppb by mass or less.
Examples of the fluorosurfactant include anionic fluorosurfactants. The anionic fluorosurfactant may be, for example, a surfactant containing fluorine atoms, the total carbon number of the portion other than the anionic group being 20 or less.
The fluorine-containing surfactant may be a surfactant having an anionic moiety with a molecular weight of 1000 or less, preferably 800 or less.
The "anionic portion" refers to a portion of the fluorosurfactant other than a cation. For example, F (CF) represented by the following formula (I) 2 ) n1 In the case of COOM, it is "F (CF) 2 ) n1 COO'.
The fluorosurfactant may be a fluorosurfactant having a log pow of 3.5 or less. The LogPOW is a partition coefficient between 1-octanol and water, and is represented by LogP [ in the formula, P represents a ratio of concentration of fluorosurfactant in octanol to concentration of fluorosurfactant in water when phase separation of octanol/water (1:1) mixed solution containing fluorosurfactant occurs ].
The LogPOW is calculated as follows: in the column: TOSOH ODS-120T columnManufactured by eastern co.) eluent: acetonitrile/0.6 mass% HClO 4 Water=1/1 (vol/vol%), flow rate: 1.0 ml/min, sample size: 300 μl, column temperature: 40 ℃, detection light: HPLC was performed on standard substances (heptanoic acid, octanoic acid, nonanoic acid, and decanoic acid) having known octanol/water partition coefficients under UV210nm conditions to prepare calibration curves for each elution time and known octanol/water partition coefficients, based on the calibration curvesCalculated from the elution time of HPLC in the sample solution.
The fluorinated surfactant is specifically a fluorinated surfactant described in U.S. patent application publication No. 2007/0015864, U.S. patent application publication No. 2007/0015865, U.S. patent application publication No. 2007/0016377, U.S. patent application publication No. 2007/0276103, U.S. patent application publication No. 2007/01179414, U.S. patent application publication No. 2007/142541, U.S. patent application publication No. 2008/0015319, U.S. patent No. 3250808, U.S. patent No. 3271341, japanese patent application laid-open No. 2003-119204, international publication No. 2005/042593, international publication No. 2008/060461, international publication No. 2007/046377, japanese patent application publication No. 2007-119526, international publication No. 2007/046482, international publication No. 2007/046345, U.S. 2014/8531, international publication No. 2013/9824, and International publication No. 2013/189826, and the like.
The anionic fluorosurfactant includes the following general formula (N) 0 )：
X n0 -Rf n0 -Y 0 (N 0 )
(wherein X is n0 H, cl or sum F. Rf (radio frequency identification) n0 An alkylene group in which part or all of H in a chain, branched or cyclic form having 3 to 20 carbon atoms is substituted with F, and the alkylene group may contain 1 or more ether linkages, and part of H may be substituted with Cl. Y is Y 0 An anionic group).
Y 0 The anionic groups of (C) may be-COOM, -SO 2 M or-SO 3 M may also be-COOM or-SO 3 M。
M is H, a metal atom, NR 7 4 Imidazolium with or without substituents, pyridinium with or without substituents or phosphonium with or without substituents, R 7 Is H or an organic group.
Examples of the metal atom include alkali metal (group 1) and alkaline earth metal (group 2), and are Na, K, and Li.
As R 7 Can be H or C 1-10 The organic radical of (2) may also be H or C 1-4 The organic group of (C) may also be H or C 1-4 Is a hydrocarbon group.
M may be H, a metal atom or NR 7 4 May also be H, alkali metal (group 1), alkaline earth metal (group 2) or NR 7 4 May also be H, na, K, li or NH 4 。
The Rf described above n0 More than 50% of H may be substituted by fluorine.
As the above general formula (N) 0 ) The compounds shown may be:
The following general formula (N) 1 )：
X n0 -(CF 2 ) m1 -Y 0 (N 1 )
(wherein X is n0 H, cl and F, m1 is an integer of 3 to 15, Y 0 A substance as defined above); the following general formula (N) 2 )：
Rf n1 -O-(CF(CF 3 )CF 2 O) m2 CFX n1 -Y 0 (N 2 )
(wherein Rf n1 Is a perfluoroalkyl group having 1 to 5 carbon atoms, m2 is an integer of 0 to 3, X n1 Is F or CF 3 ，Y 0 A substance as defined above); the following general formula (N) 3 )：
Rf n2 (CH 2 ) m3 -(Rf n3 ) q -Y 0 (N 3 )
(wherein Rf n2 Is a partially or fully fluorinated alkyl group having 1 to 13 carbon atoms and optionally containing an ether bond, m3 is an integer of 1 to 3, rf n3 Is a linear or branched perfluoroalkylene group having 1 to 3 carbon atoms, q is 0 or 1, Y 0 A substance as defined above); the following general formula (N) 4 )：
Rf n4 -O-(CY n1 Y n2 ) p CF 2 -Y 0 (N 4 )
(wherein Rf n4 Is a linear or branched partially or fully fluorinated alkyl group having 1 to 12 carbon atoms and containing an ether bond and/or a chlorine atom, Y n1 And Y n2 Identical or different, H or F, p being 0 or 1, Y 0 A substance as defined above); of the general formula (N) 5 )：
[ chemical 13]
(wherein X is n2 、X n3 And X n4 The alkyl group may be the same or different, and is H, F or a linear or branched partially or fully fluorinated alkyl group having 1 to 6 carbon atoms and containing an ether bond. Rf (radio frequency identification) n5 Is a linear or branched partially or completely fluorinated alkylene group having 1 to 3 carbon atoms and containing an ether bond, L is a linking group, Y 0 Is a substance as defined above. Wherein X is n2 、X n3 、X n4 And Rf n5 The total carbon number of (2) is 18 or less).
As the above general formula (N) 0 ) More specifically, examples of the compounds represented by the formula (I) include perfluorocarboxylic acid (I) represented by the following general formula (I), ω -H perfluorocarboxylic acid (II) represented by the following general formula (II), perfluoroether carboxylic acid (III) represented by the following general formula (III), perfluoroalkyl alkylene carboxylic acid (IV) represented by the following general formula (IV), perfluoroalkoxy fluorocarboxylic acid (V) represented by the following general formula (V), perfluoroalkyl sulfonic acid (VI) represented by the following general formula (VI), ω -H perfluorosulfonic acid (VII) represented by the following general formula (VII), perfluoroalkyl alkylene sulfonic acid (VIII) represented by the following general formula (VIII), alkyl alkylene carboxylic acid (IX) represented by the following general formula (IX), fluorocarboxylic acid (X) represented by the following general formula (X), alkoxy fluorosulfonic acid (XI) represented by the following general formula (XII), compound (XII) represented by the following general formula (XIII), and the like.
The perfluorocarboxylic acid (I) is represented by the following general formula (I)
F(CF 2 ) n1 COOM (I)
(wherein n1 is an integer of 3 to 14, M is H, a metal atom, NR 7 4 Imidazolium with or without substituents, pyridinium with or without substituents or phosphonium with or without substituents, R 7 Is H or an organic group).
The omega-H perfluorocarboxylic acid (II) is represented by the following general formula (II)
H(CF 2 ) n2 COOM (II)
(wherein n2 is an integer of 4 to 15, and M is a substance defined above).
The perfluoroether carboxylic acid (III) is represented by the following general formula (III)
Rf 1 -O-(CF(CF 3 )CF 2 O) n3 CF(CF 3 )COOM (III)
(wherein Rf 1 A perfluoroalkyl group having 1 to 5 carbon atoms, n3 is an integer of 0 to 3, and M is a substance defined above).
The perfluoroalkyl alkylene carboxylic acid (IV) is represented by the following general formula (IV)
Rf 2 (CH 2 ) n4 Rf 3 COOM (IV)
(wherein Rf 2 Is a perfluoroalkyl group having 1 to 5 carbon atoms, rf 3 A linear or branched perfluoroalkylene group having 1 to 3 carbon atoms, n4 is an integer of 1 to 3, and M is a substance as defined above).
The above-mentioned alkoxyfluorocarboxylic acid (V) is represented by the following general formula (V)
Rf 4 -O-CY 1 Y 2 CF 2 -COOM (V)
(wherein Rf 4 Is a linear or branched partially or fully fluorinated alkyl group having 1 to 12 carbon atoms and containing an ether bond and/or a chlorine atom, Y 1 And Y 2 The same or different, H or F, M is a substance as defined above).
The perfluoroalkyl sulfonic acid (VI) is represented by the following general formula (VI)
F(CF 2 ) n5 SO 3 M (VI)
(wherein n5 is an integer of 3 to 14, and M is a substance defined above).
The omega-H perfluorosulfonic acid (VII) is represented by the following general formula (VII)
H(CF 2 ) n6 SO 3 M(VII)
(wherein n6 is an integer of 4 to 14, and M is a substance defined above).
The perfluoroalkyl alkylene sulfonic acid (VIII) is represented by the following general formula (VIII)
Rf 5 (CH 2 ) n7 SO 3 M (VIII)
(wherein Rf 5 A perfluoroalkyl group having 1 to 13 carbon atoms, n7 is an integer of 1 to 3, and M is a substance defined above).
The above-mentioned alkyl alkylene carboxylic acid (IX) is represented by the following general formula (IX)
Rf 6 (CH 2 ) n8 COOM (IX)
(wherein Rf 6 A linear or branched partially or completely fluorinated alkyl group having 1 to 13 carbon atoms and optionally containing an ether bond, n8 is an integer of 1 to 3, and M is as defined above).
The fluorocarboxylic acid (X) is represented by the following general formula (X)
Rf 7 -O-Rf 8 -O-CF 2 -COOM (X)
(wherein Rf 7 Is a linear or branched partially or fully fluorinated alkyl group having 1 to 6 carbon atoms and optionally containing an ether bond and/or a chlorine atom, rf 8 A linear or branched partially or completely fluorinated alkyl group having 1 to 6 carbon atoms, and M is a substance defined above).
The above alkoxy fluorosulfonic acid (XI) is represented by the following general formula (XI)
Rf 9 -O-CY 1 Y 2 CF 2 -SO 3 M (XI)
(wherein Rf 9 Is a linear or branched partially or completely fluorinated alkyl group having 1 to 12 carbon atoms and optionally containing chlorine, Y 1 And Y 2 Identical or different, H or F, M being a substance as defined above)And (3) representing.
The above compound (XII) is represented by the following general formula (XII):
[ chemical 14]
(wherein X is 1 、X 2 And X 3 H, F and a linear or branched partially or completely fluorinated alkyl group having 1 to 6 carbon atoms which may contain an ether bond, rf 10 Is a perfluoroalkylene group having 1 to 3 carbon atoms, L is a linking group, Y 0 An anionic group).
Y 0 Can be-COOM, -SO 2 M or-SO 3 M may also be-SO 3 M or COOM (wherein M is as defined above).
Examples of the L include a single bond and a partially or fully fluorinated alkylene group having 1 to 10 carbon atoms which may contain an ether bond.
The above compound (XIII) is represented by the following general formula (XIII):
Rf 11 -O-(CF 2 CF(CF 3 )O) n9 (CF 2 O) n10 CF 2 COOM (XIII)
(wherein Rf 11 Fluoroalkyl containing chlorine and having 1 to 5 carbon atoms, n9 is an integer of 0 to 3, n10 is an integer of 0 to 3, and M is a substance as defined above). As the compound (XIII), CF may be mentioned 2 ClO(CF 2 CF(CF 3 )O) n9 (CF 2 O) n10 CF 2 COONH 4 (a mixture of average molecular weights of 750, wherein n9 and n10 are as defined above).
As described above, examples of the anionic fluorosurfactant include carboxylic acid-based surfactants and sulfonic acid-based surfactants.
The fluorosurfactant may be 1 kind of fluorosurfactant or a mixture of 2 or more kinds of fluorosurfactants.
The fluorosurfactant may be a compound represented by the following formula. The fluorosurfactant can also be a mixture of these compounds. In one embodiment of the above polymerization, the fluoromonomer is polymerized in the substantial absence of a compound represented by the following formula.
F(CF 2 ) 7 COOM、
F(CF 2 ) 5 COOM、
H(CF 2 ) 6 COOM、
H(CF 2 ) 7 COOM、
CF 3 O(CF 2 ) 3 OCHFCF 2 COOM、
C 3 F 7 OCF(CF 3 )CF 2 OCF(CF 3 )COOM、
CF 3 CF 2 CF 2 OCF(CF 3 )COOM、
CF 3 CF 2 OCF 2 CF 2 OCF 2 COOM、
C 2 F 5 OCF(CF 3 )CF 2 OCF(CF 3 )COOM、
CF 3 OCF(CF 3 )CF 2 OCF(CF 3 )COOM、
CF 2 ClCF 2 CF 2 OCF(CF 3 )CF 2 OCF 2 COOM、
CF 2 ClCF 2 CF 2 OCF 2 CF(CF 3 )OCF 2 COOM、
CF 2 ClCF(CF 3 )OCF(CF 3 )CF 2 OCF 2 COOM、
CF 2 ClCF(CF 3 )OCF 2 CF(CF 3 )OCF 2 COOM、
[ 15]
(in the formula, M is H, a metal atom, NR 7 4 An imidazolium with or without substituents, a pyridinium with or without substituents, or a phosphonium with or without substituents. R is R 7 Is H or an organic group. )
By the polymerization, an aqueous dispersion containing the fluoropolymer can be obtained. The fluoropolymer is usually present in a concentration of 8 to 50% by mass of the aqueous dispersion obtained by the polymerization. In the aqueous dispersion, the concentration of the fluoropolymer is preferably 10% by mass, more preferably 15% by mass, and the concentration of the fluoropolymer is preferably 40% by mass, more preferably 35% by mass.
The fluoropolymer content in the aqueous dispersion was obtained by drying 1g of the aqueous dispersion in a blow dryer at 150℃for 60 minutes, measuring the mass of the heated residue, and calculating the ratio of the mass of the heated residue to the mass of the aqueous dispersion (1 g) as a percentage.
< fluoropolymer >
According to the production method 1 of the present invention, a fluoropolymer having a content of polymerized units based on a perfluoromonomer of 90 mol% or more relative to the total polymerized units of the fluoropolymer is obtained. The partially fluorinated rubber is not contained in the fluoropolymer having a content of polymerized units of 90 mol% or more based on the perfluorinated monomer.
The above fluoropolymers preferably have an ion exchange rate (IXR) higher than 53. Preferred fluoropolymers have no ionic groups at all, or have a limited number of ionic groups that can give an ion exchange rate of greater than about 100. The ion exchange rate of the fluoropolymer is preferably 1000 or more, more preferably 2000 or more, and still more preferably 5000 or more.
The fluorine substitution rate of the fluoropolymer obtained by the production method 1 of the present invention is preferably 90 to 100% by mass, more preferably 95% by mass or more. The fluoropolymer may also be a perfluorinated resin or perfluoroelastomer.
The fluorine substitution rate can be calculated by the following formula.
Fluorine substitution ratio (%) = (number of fluorine atoms bonded to carbon atoms constituting the fluorine-containing polymer)/((number of hydrogen atoms bonded to carbon atoms constituting the fluorine-containing polymer) + (number of fluorine atoms and chlorine atoms bonded to carbon atoms constituting the fluorine-containing polymer)) ×100
The fluoropolymer obtained by the production method 1 of the present invention includes: polytetrafluoroethylene [ PTFE ]; melt processible fluororesin such as TFE/HFP copolymer [ FEP ], TFE/perfluoro (alkyl vinyl ether) copolymer [ PFA, MFA, etc. ], TFE/perfluoro (alkyl allyl ether) copolymer, electrolyte polymer precursor, etc.; a perfluoroelastomer; etc.
Among them, at least 1 selected from the group consisting of PTFE and perfluoroelastomers is preferable as the fluoropolymer.
The fluoropolymer may have a core-shell structure. Examples of the fluoropolymer having a core-shell structure include PTFE in which a core of PTFE having a high molecular weight and a PTFE having a lower molecular weight or a modified PTFE shell are contained in particles. Examples of such PTFE include PTFE described in Japanese patent application laid-open No. 2005-527652.
As the core-shell structure, the following structure can be used, for example.
And (3) core: TFE homopolymer shell: TFE homopolymers
And (3) core: modified PTFE shell: TFE homopolymers
And (3) core: modified PTFE shell: modified PTFE
And (3) core: TFE homopolymer shell: modified PTFE
And (3) core: low molecular weight PTFE shell: high molecular weight PTFE
And (3) core: high molecular weight PTFE shell: low molecular weight PTFE
In the fluoropolymer having the core-shell structure, the lower limit of the proportion of the core is preferably 0.5 mass%, more preferably 1.0 mass%, further preferably 3.0 mass%, particularly preferably 5.0 mass%, and most preferably 10.0 mass%. The upper limit of the proportion of the core is preferably 99.5 mass%, more preferably 99.0 mass%, further preferably 98.0 mass%, further preferably 97.0 mass%, particularly preferably 95.0 mass%, and most preferably 90.0 mass%.
In the fluoropolymer having the core-shell structure, the lower limit of the proportion of the shell is preferably 0.5 mass%, more preferably 1.0 mass%, further preferably 3.0 mass%, particularly preferably 5.0 mass%, and most preferably 10.0 mass%. The upper limit of the proportion of the shell is preferably 99.5 mass%, more preferably 99.0 mass%, further preferably 98.0 mass%, further preferably 97.0 mass%, particularly preferably 95.0 mass%, and most preferably 90.0 mass%.
In the fluoropolymer having the core-shell structure, the core or the shell may have a structure of 2 layers or more. For example, the fluoropolymer may have a 3-layer structure having a core portion of modified PTFE, a core outer layer portion of TFE homopolymer, and a shell of modified PTFE.
The fluoropolymer having the core-shell structure may be a fluoropolymer having a plurality of cores in one particle of the fluoropolymer.
The PTFE (I) and the melt-processible fluororesin (II) and the perfluoroelastomer (III) which are suitably produced by the production method of the present invention are preferably produced in the following manner.
(I)PTFE
In the production method 1 of the present invention, PTFE (TFE polymer) as a fluoropolymer can be produced by polymerizing TFE as a perfluoro monomer. The PTFE is preferably non-melt processible PTFE.
In the production process of the present invention, TFE is usually polymerized at a polymerization temperature of 10℃to 150℃and a polymerization pressure of 0.05MPaG to 5 MPaG. For example, the polymerization temperature is more preferably 30℃or higher, and still more preferably 50℃or higher. Further, the temperature is more preferably 120℃or lower, and still more preferably 100℃or lower. The polymerization pressure is more preferably 0.3MPaG or more, still more preferably 0.5MPaG or more, still more preferably 5.0MPaG or less, still more preferably 3.0MPaG or less. In particular, from the viewpoint of increasing the amount of the fluoropolymer obtained, it is preferably 1.0MPaG or more, more preferably 1.2MPaG or more, still more preferably 1.5MPaG or more, and still more preferably 2.0MPaG or more.
In one embodiment, in the polymerization, pure water is charged into a pressure-resistant reaction vessel equipped with a stirrer, TFE is charged after deoxidization to a predetermined temperature, and a polymerization initiator is added to initiate the reaction. When the pressure decreases with the progress of the reaction, additional TFE is added continuously or intermittently to maintain the initial pressure. The supply of TFE was stopped at the time when the predetermined amount of TFE was supplied, TFE in the reaction vessel was purged, the temperature was returned to room temperature, and the reaction was terminated. In order to prevent the pressure from decreasing, additional TFE may be added continuously or intermittently.
In the production of the TFE Polymer (PTFE), various known modifying monomers may be used in combination. In the present invention, the TFE polymer is a concept including not only TFE homopolymer but also a non-melt-processible substance (hereinafter referred to as "modified PTFE") which is a copolymer of TFE and a modifying monomer.
The modifying monomer is not particularly limited as long as it can be copolymerized with TFE, and examples thereof include fluoromonomers and non-fluoromonomers. The number of the modifying monomers used may be 1 or 2 or more.
The non-fluorine-containing monomer is not particularly limited, and examples thereof include general formula:
CH 2 ＝CR Q1 -LR Q2
(wherein R is Q1 Represents a hydrogen atom or an alkyl group. L represents a single bond, -CO-O-, -O-CO-, or-O-. * Representing and R Q2 Is used for the bonding position of the substrate. R is R Q2 Represents a hydrogen atom, an alkyl group or a nitrile group).
Examples of the non-fluorine-containing monomer include methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, butyl acrylate, butyl methacrylate, hexyl methacrylate, cyclohexyl methacrylate, vinyl acetate, acrylic acid, methacrylic acid, acrylonitrile, methacrylonitrile, ethyl vinyl ether, and cyclohexyl vinyl ether. Among them, butyl methacrylate, vinyl acetate and acrylic acid are preferable as the non-fluorine-containing monomer.
Examples of the fluorine-containing monomer include perfluoroolefins such as hexafluoropropylene [ HFP ]; hydrofluoroolefins such as trifluoroethylene and vinylidene fluoride [ VDF ]; perhaloolefins such as chlorotrifluoroethylene; perfluorovinyl ether; (perfluoroalkyl) ethylene; perfluoro allyl ether; etc.
The perfluorovinyl ether is not particularly limited, and examples thereof include the general formula (a):
CF 2 ＝CF-ORf(A)
(wherein Rf represents a perfluorinated organic group) and the like. In the present invention, the term "perfluorinated organic group" refers to an organic group in which all hydrogen atoms bonded to carbon atoms are replaced with fluorine atoms. The perfluorinated organic group may have ether oxygen.
As the perfluorovinyl ether, for example, there may be mentioned perfluoro (alkyl vinyl ether) wherein Rf in the general formula (A) is a perfluoroalkyl group having 1 to 10 carbon atoms [ PAVE ]. The number of carbon atoms of the perfluoroalkyl group is preferably 1 to 5.
Examples of the perfluoroalkyl group in PAVE include a perfluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluorobutyl group, a perfluoropentyl group, and a perfluorohexyl group.
Further examples of the perfluorovinyl ether include a monomer in which Rf is a perfluoro (alkoxyalkyl) group having 4 to 9 carbon atoms in the general formula (A), and Rf is the following formula:
[ 16]
(wherein m represents 0 or an integer of 1 to 4), and Rf is represented by the following formula:
CF 3 CF 2 CF 2 -(O-CF(CF 3 )-CF 2 ) n -
(wherein n represents an integer of 1 to 4), and the like.
As the hydrogen-containing fluoroolefin, CH can be mentioned 2 ＝CF 2 、CFH＝CH 2 、CFH＝CF 2 、CH 2 ＝CFCF 3 、CH 2 ＝CHCF 3 、CHF＝CHCF 3 (E-body), chf=chcf 3 (Z body), and the like.
The (perfluoroalkyl) ethylene (PFAE) is not particularly limited, and examples thereof include (perfluorobutyl) ethylene (PFBE) and (perfluorohexyl) ethylene.
Examples of the perfluoroallyl ether include
A general formula: CF (compact flash) 2 ＝CF-CF 2 -ORf
(wherein Rf represents a perfluorinated organic group).
Rf of the above formula is the same as Rf of the formula (A). Rf is preferably a perfluoroalkyl group having 1 to 10 carbon atoms or a perfluoroalkoxyalkyl group having 1 to 10 carbon atoms. As the perfluoroallyl ether, it is preferably selected from the group consisting of CF 2 ＝CF-CF 2 -O-CF 3 、CF 2 ＝CF-CF 2 -O-C 2 F 5 、CF 2 ＝CF-CF 2 -O-C 3 F 7 And CF (compact F) 2 ＝CF-CF 2 -O-C 4 F 9 At least 1 selected from the group consisting of CF, more preferably 2 ＝CF-CF 2 -O-C 2 F 5 、CF 2 ＝CF-CF 2 -O-C 3 F 7 And CF (compact F) 2 ＝CF-CF 2 -O-C 4 F 9 At least 1 of the group consisting of CF is further preferred 2 ＝CF-CF 2 -O-CF 2 CF 2 CF 3 。
The modified monomer (3) having a monomer reactivity ratio of 0.1 to 8 is also preferably exemplified as the modified monomer. By the presence of the modifying monomer (3), PTFE particles having a small particle diameter can be obtained, and an aqueous dispersion having high dispersion stability can be obtained.
Here, the monomer reactivity ratio in copolymerization with TFE is a value obtained as follows: when the growth radical is smaller than the TFE-based repeating unit, the value obtained by dividing the rate constant at which the growth radical reacts with TFE by the rate constant at which the growth radical reacts with the modifying monomer is the above-mentioned monomer reactivity ratio. The lower this value, the higher the reactivity of the modifying monomer with TFE. The monomer reactivity ratio can be calculated as follows: TFE was copolymerized with a modifying monomer to obtain the composition of the resulting polymer immediately after the initiation, and the composition was calculated from the Finerman-Ross formula.
The copolymerization was carried out using 3600g of deionized and degassed water, 1000 mass ppm of ammonium perfluorooctanoate relative to the water, and 100g of paraffin wax in a stainless steel autoclave having an internal volume of 6.0L, and a pressure of 0.78MPaG and a temperature of 70 ℃. 0.05g, 0.1g, 0.2g, 0.5g, and 1.0g of the modified monomer were added to the reactor, respectively, and 0.072g of ammonium persulfate (20 mass ppm relative to water) was added thereto, and TFE was continuously fed so as to maintain the polymerization pressure of 0.78 MPaG. When the TFE charge reached 1000g, stirring was stopped and the pressure was removed until the reactor reached atmospheric pressure. After cooling, paraffin wax is separated, whereby an aqueous dispersion comprising the resulting polymer is obtained. The aqueous dispersion was stirred to precipitate a polymer, and dried at 150 ℃. The composition of the resulting polymer was calculated by appropriately combining NMR, FT-IR, elemental analysis, and fluorescent X-ray analysis according to the kind of monomer.
The modified monomer (3) having a monomer reactivity ratio of 0.1 to 8 is preferably at least 1 selected from the group consisting of modified monomers represented by formulas (3 a) to (3 d).
CH 2 ＝CH-Rf 1 (3a)
(wherein Rf 1 Is a perfluoroalkyl group having 1 to 10 carbon atoms. )
CF 2 ＝CF-O-Rf 2 (3b)
(wherein Rf 2 Is a perfluoroalkyl group having 1 to 2 carbon atoms. )
CF 2 ＝CF-O-(CF 2 ) n CF＝CF 2 (3c)
(wherein n is 1 or 2.)
[ chemical 17]
(wherein X is 3 And X 4 Is F, cl or methoxy, Y is of the formula Y1 or Y2. )
[ chemical 18]
-CF＝CE- (Y1)
(in the formula Y2, Z and Z' are F or fluoroalkyl groups having 1 to 3 carbon atoms.)
The content of the modified monomer (3) unit is preferably in the range of 0.00001 to 1.0 mass% relative to the total polymerized units of PTFE. The lower limit is more preferably 0.0001 mass%, still more preferably 0.0005 mass%, still more preferably 0.001 mass%, still more preferably 0.005 mass%. The upper limit is preferably 0.90 mass%, 0.50 mass%, 0.40 mass%, 0.30 mass%, 0.20 mass%, 0.15 mass%, 0.10 mass%, 0.08 mass%, 0.05 mass%, or 0.01 mass%.
As the above-mentioned modifying monomer, at least 1 selected from the group consisting of hexafluoropropylene, chlorotrifluoroethylene, vinylidene fluoride, perfluoro (alkyl vinyl ether), (perfluoroalkyl) ethylene, and a modifying monomer having a functional group and a hydrophilic group capable of undergoing radical polymerization is preferable since an aqueous dispersion having a small average primary particle diameter of primary particles, a small aspect ratio of primary particles, and excellent stability can be obtained. By using the modified monomer, an aqueous dispersion of PTFE having a smaller average primary particle diameter, a small aspect ratio of primary particles, and excellent dispersion stability can be obtained. In addition, an aqueous dispersion with little undeposited polymer can be obtained.
From the viewpoint of reactivity with TFE, the above-mentioned modifying monomer preferably contains at least 1 selected from the group consisting of hexafluoropropylene, perfluoro (alkyl vinyl ether) and (perfluoroalkyl) ethylene.
More preferably at least 1 selected from the group consisting of hexafluoropropylene, perfluoro (methyl vinyl ether), perfluoro (propyl vinyl ether), (perfluorobutyl) ethylene, (perfluorohexyl) ethylene and (perfluorooctyl) ethylene.
The total amount of hexafluoropropylene units, perfluoro (alkyl vinyl ether) units and (perfluoroalkyl) ethylene units is preferably in the range of 0.00001 to 1 mass% relative to the total polymerized units of PTFE. The lower limit of the total amount is more preferably 0.0001 mass%, still more preferably 0.0005 mass%, still more preferably 0.001 mass%, still more preferably 0.005 mass%. The upper limit is preferably 0.80 mass%, 0.70 mass%, 0.50 mass%, 0.40 mass%, 0.30 mass%, 0.20 mass%, 0.15 mass%, 0.10 mass%, 0.08 mass%, 0.05 mass%, or 0.01 mass%.
The above-mentioned modifying monomer also preferably contains a modifying monomer having a functional group capable of reacting by radical polymerization and a hydrophilic group (hereinafter referred to as "modifying monomer (a)").
By the presence of the modifying monomer (a), PTFE particles having a small primary particle diameter can be obtained, and an aqueous dispersion having high dispersion stability can be obtained. In addition, the amount of undeposited polymer can be reduced. Further, the aspect ratio of the primary particles can be reduced.
The amount of the modifying monomer (a) used is preferably an amount exceeding 0.1 mass ppm equivalent to the aqueous medium, more preferably an amount exceeding 0.5 mass ppm, still more preferably an amount exceeding 1.0 mass ppm, still more preferably 5 mass ppm or more, and particularly preferably 10 mass ppm or more. If the amount of the modifying monomer (a) is too small, the average primary particle diameter of the obtained PTFE may not be reduced.
The amount of the modifying monomer (A) may be in the above range, and for example, the upper limit may be 5000 mass ppm. In the above production method, the modifying monomer (a) may be added to the system during the reaction in order to improve the stability of the aqueous dispersion during or after the reaction.
Since the modified monomer (a) has high water solubility, even if the unreacted modified monomer (a) remains in the aqueous dispersion, it is easily removed in the concentration step or the precipitation/washing step.
The above-mentioned modifying monomer (a) is introduced into the resultant polymer during the polymerization, but since the concentration of the modifying monomer (a) itself in the polymerization system is low, the amount of the modifying monomer (a) introduced into the polymer is small, and thus there is no problem that the heat resistance of PTFE is lowered or coloring after firing is caused.
Examples of the hydrophilic group in the modified monomer (A) include-NH 2 、-PO 3 M、-OPO 3 M、-SO 3 M、-OSO 3 M, -COOM (in the formulae, M is H, a metal atom, NR) 7y 4 Imidazolium with or without substituents, pyridinium with or without substituents or phosphonium with or without substituents, R 7y H or an organic group may be the same or different. Any 2 may be bonded to each other to form a ring). As the above hydrophilic group, among them, preferred is-SO 3 M or-COOM. As R 7y The organic group in (2) is preferably an alkyl group. As R 7y Preferably H or C 1-10 More preferably H or C 1-4 Further preferably H or C 1-4 Is a hydrocarbon group.
The metal atom may be a 1-valent or 2-valent metal atom, and examples thereof include alkali metal (group 1), alkaline earth metal (group 2), and the like, and Na, K, and Li are preferable.
Examples of the "functional group capable of undergoing radical polymerization" in the modified monomer (a) include groups having an ethylenically unsaturated bond such as a vinyl group and an allyl group. The group having an ethylenic unsaturated bond may be represented by the following formula:
CX e X g ＝CX f R-
(wherein X is e 、X f And X g Each independently F, cl, H, CF 3 、CF 2 H、CFH 2 Or CH (CH) 3 The method comprises the steps of carrying out a first treatment on the surface of the R is a linking group). Examples of the linking group for R include R as described below a Is a linking group of (a). Preferable examples include-ch=ch 2 、-CF＝CH 2 、-CH＝CF 2 、-CF＝CF 2 、-CH 2 -CH＝CH 2 、-CF 2 -CF＝CH 2 、-CF 2 -CF＝CF 2 、-(C＝O)-CH＝CH 2 、-(C＝O)-CF＝CH 2 、-(C＝O)-CH＝CF 2 、-(C＝O)-CF＝CF 2 、-(C＝O)-C(CH 3 )＝CH 2 、-(C＝O)-C(CF 3 )＝CH 2 、-(C＝O)-C(CH 3 )＝CF 2 、-(C＝O)-C(CF 3 )＝CF 2 、-O-CH 2 -CH＝CH 2 、-O-CF 2 -CF＝CH 2 、-O-CH 2 -CH＝CF 2 、-O-CF 2 -CF＝CF 2 And the like having an unsaturated bond.
Since the modified monomer (a) has a functional group capable of undergoing radical polymerization, when used in the polymerization, it reacts with the fluorine-containing monomer at the initial stage of the polymerization, and it is presumed that the modified monomer (a) has a hydrophilic group derived from the modified monomer (a), and particles having high stability can be formed. Therefore, if polymerization is carried out in the presence of the above-mentioned modifying monomer (a), it is considered that the number of particles increases.
In the polymerization, the number of the modifying monomers (A) may be 1 or 2 or more.
In the polymerization, as the modifying monomer (a), a compound having an unsaturated bond may be used.
The modifying monomer (A) is preferably of the formula (4):
CX i X k ＝CX j R a -(CZ 1 Z 2 ) k -Y 3 (4)
(wherein X is i 、X j And X k Each independently F, cl, H or CF 3 ；Y 3 Is a hydrophilic group; r is R a Is a linking group; z is Z 1 And Z 2 Each independently is H, F or CF 3 K is 0 or 1).
Examples of the hydrophilic group include-NH 2 、-PO 3 M、-OPO 3 M、-SO 3 M、-OSO 3 M, -COOM (in the formulae, M is H, a metal atom, NR) 7y 4 Imidazolium with or without substituents, pyridinium with or without substituents or phosphonium with or without substituents, R 7y H or an organic group may be the same or different. Any 2 may be bonded to each other to form a ring). As the above hydrophilic group, among them, preferred is-SO 3 M or-COOM. As R 7y The organic group in (2) is preferably an alkyl group. As R 7y Preferably H or C 1-10 More preferably H or C 1-4 Further preferably H or C 1-4 Is a hydrocarbon group. The metal atom may be a 1-valent or 2-valent metal atom, and examples thereof include alkali metal (group 1), alkaline earth metal (group 2), and the like, and Na, K, and Li are preferable.
By using the modified monomer (a), an aqueous dispersion having a smaller average primary particle diameter and more excellent stability can be obtained. In addition, the aspect ratio of the primary particles can be further reduced.
R is as described above a Is a linking group. In the present invention, "linking group" refers to a divalent linking group. The linking group may be a single bond, preferably contains at least 1 carbon atom, and the number of carbon atoms may be 2 or more, 4 or more, 8 or more, 10 or more, or 20 or more. The upper limit is not limited, and may be, for example, 100 or less, or 50 or less.
The linking group may be a chain or branched, cyclic or acyclic structure, saturated or unsaturated, substituted or unsubstituted, may contain 1 or more hetero atoms selected from the group consisting of sulfur, oxygen and nitrogen as desired, and may contain 1 or more functional groups selected from the group consisting of esters, amides, sulfonamides, carbonyl groups, carbonates, carbamates, ureas and carbamates as desired. The linking group contains no carbon atom and may be a chain hetero atom such as oxygen, sulfur or nitrogen.
R is as described above a Preferably a chain heteroatom such as oxygen, sulfur, nitrogen, or a 2-valent organic group.
R a In the case of a 2-valent organic group, the hydrogen atom bonded to the carbon atom may be replaced with a halogen other than fluorine, for example, chlorine, and may or may not contain a double bond. In addition, R a The compound may be either chain-shaped or branched, or cyclic or acyclic. In addition, R a Functional groups (e.g., esters, ethers, ketones, amines, halides, etc.) may be included.
In addition, R a Can be a non-fluorine 2-valent organic group, orIs a partially fluorinated or perfluorinated 2-valent organic group.
As R a It may be, for example: hydrocarbon groups having no fluorine atom bonded to a carbon atom; a hydrocarbon group in which a part of hydrogen atoms bonded to carbon atoms is substituted with fluorine atoms; hydrocarbon groups in which all hydrogen atoms bonded to carbon atoms are substituted with fluorine atoms; hydrocarbon groups containing- (c=o) -, - (c=o) -O-, or ether linkages, which may contain oxygen atoms, may contain double bonds, or may contain functional groups.
R a Preferably, the hydrocarbon group is a hydrocarbon group having 1 to 100 carbon atoms and containing or not containing- (C=O) -, - (C=O) -O-or an ether bond, and in the hydrocarbon group, part or all of hydrogen atoms bonded to carbon atoms may be substituted with fluorine.
As R a Preferably selected from- (CH) 2 ) a -、-(CF 2 ) a -、-O-(CF 2 ) a -、-(CF 2 ) a -O-(CF 2 ) b -、-O(CF 2 ) a -O-(CF 2 ) b -、-(CF 2 ) a -[O-(CF 2 ) b ] c -、-O(CF 2 ) a -[O-(CF 2 ) b ] c -、-[(CF 2 ) a -O] b -[(CF 2 ) c -O] d -、-O[(CF 2 ) a -O] b -[(CF 2 ) c -O] d -、-O-[CF 2 CF(CF 3 )O] a -(CF 2 ) b -、-(C＝O)-、-(C＝O)-O-、-(C＝O)-(CH 2 ) a -、-(C＝O)-(CF 2 ) a -、-(C＝O)-O-(CH 2 ) a -、-(C＝O)-O-(CF 2 ) a -、-(C＝O)-[(CH 2 ) a -O] b -、-(C＝O)-[(CF 2 ) a -O] b -、-(C＝O)-O[(CH 2 ) a -O] b -、-(C＝O)-O[(CF 2 ) a -O] b -、-(C＝O)-O[(CH 2 ) a -O] b -(CH 2 ) c -、-(C＝O)-O[(CF 2 ) a -O] b -(CF 2 ) c -、-(C＝O)-(CH 2 ) a -O-(CH 2 ) b -、-(C＝O)-(CF 2 ) a -O-(CF 2 ) b -、-(C＝O)-O-(CH 2 ) a -O-(CH 2 ) b -、-(C＝O)-O-(CF 2 ) a -O-(CF 2 ) b -、-(C＝O)-O-C 6 H 4 -and combinations thereof.
Wherein a, b, c and d are independently at least 1 or more. a. b, c, and d independently may be 2 or more, 3 or more, 4 or more, 10 or more, or 20 or more. a. The upper limits of b, c and d are, for example, 100.
As R a Preferred examples thereof include-CF 2 -O-、-CF 2 -O-CF 2 -、-CF 2 -O-CH 2 -、-CF 2 -O-CH 2 CF 2 -、-CF 2 -O-CF 2 CF 2 -、-CF 2 -O-CF 2 CH 2 -、-CF 2 -O-CF 2 CF 2 CH 2 -、-CF 2 -O-CF(CF 3 )-、-CF 2 -O-CF(CF 3 )CF 2 -、-CF 2 -O-CF(CF 3 )CF 2 -O-、-CF 2 -O-CF(CF 3 )CH 2 -、-(C＝O)-、-(C＝O)-O-、-(C＝O)-(CH 2 )-、-(C＝O)-(CF 2 )-、-(C＝O)-O-(CH 2 )-、-(C＝O)-O-(CF 2 )-、-(C＝O)-[(CH 2 ) 2 -O] n -、-(C＝O)-[(CF 2 ) 2 -O] n -、-(C＝O)-O[(CH 2 ) 2 -O] n -、-(C＝O)-O[(CF 2 ) 2 -O] n -、-(C＝O)-O[(CH 2 ) 2 -O] n -(CH 2 )-、-(C＝O)-O[(CF 2 ) 2 -O] n -(CF 2 )-、-(C＝O)-(CH 2 ) 2 -O-(CH 2 )-、-(C＝O)-(CF 2 ) 2 -O-(CF 2 )-、-(C＝O)-O-(CH 2 ) 2 -O-(CH 2 )-、-(C＝O)-O-(CF 2 ) 2 -O-(CF 2 )-、-(C＝O)-O-C 6 H 4 -and the like. Wherein, specifically, R is as described above a preferably-CF 2 -O-、-CF 2 -O-CF 2 -、-CF 2 -O-CF 2 CF 2 -、-CF 2 -O-CF(CF 3 )-、-CF 2 -O-CF(CF 3 )CF 2 -、-CF 2 -O-CF(CF 3 )CF 2 -O-、-(C＝O)-、-(C＝O)-O-、-(C＝O)-(CH 2 )-、-(C＝O)-O-(CH 2 )-、-(C＝O)-O[(CH 2 ) 2 -O] n -、-(C＝O)-O[(CH 2 ) 2 -O] n -(CH 2 )-、-(C＝O)-(CH 2 ) 2 -O-(CH 2 ) -, or- (c=o) -O-C 6 H 4 -。
In the above formula, n is an integer of 1 to 10.
as-R in the general formula (4) a -(CZ 1 Z 2 ) k -, preferably-CF 2 -O-CF 2 -、-CF 2 -O-CF(CF 3 )-、-CF 2 -O-C(CF 3 ) 2 -、-CF 2 -O-CF 2 -CF 2 -、-CF 2 -O-CF 2 -CF(CF 3 )-、-CF 2 -O-CF 2 -C(CF 3 ) 2 -、-CF 2 -O-CF 2 CF 2 -CF 2 -、-CF 2 -O-CF 2 CF 2 -CF(CF 3 )-、-CF 2 -O-CF 2 CF 2 -C(CF 3 ) 2 -、-CF 2 -O-CF(CF 3 )-CF 2 -、-CF 2 -O-CF(CF 3 )-CF(CF 3 )-、-CF 2 -O-CF(CF 3 )-C(CF 3 ) 2 -、-CF 2 -O-CF(CF 3 )CF 2 -CF 2 -、-CF 2 -O-CF(CF 3 )CF 2 -CF(CF 3 )-、-CF 2 -O-CF(CF 3 )CF 2 -C(CF 3 ) 2 -、-CF 2 -O-CF(CF 3 )CF 2 -O-CF 2 -、-CF 2 -O-CF(CF 3 )CF 2 -O-CF(CF 3 )-、-CF 2 -O-CF(CF 3 )CF 2 -O-C(CF 3 ) 2 -、-(C＝O)-、-(C＝O)-O-、-(C＝O)-(CH 2 )-、-(C＝O)-(CF 2 )-、-(C＝O)-O-(CH 2 )-、-(C＝O)-O-(CF 2 )-、-(C＝O)-[(CH 2 ) 2 -O] n -(CH 2 )-、-(C＝O)-[(CF 2 ) 2 -O] n -(CF 2 )-、-(C＝O)-[(CH 2 ) 2 -O] n -(CH 2 )-(CH 2 )-、-(C＝O)-[(CF 2 ) 2 -O] n -(CF 2 )-(CF 2 )-、-(C＝O)-O[(CH 2 ) 2 -O] n -(CF 2 )-、-(C＝O)-O[(CH 2 ) 2 -O] n -(CH 2 )-(CH 2 )-、-(C＝O)-O[(CF 2 ) 2 -O] n -(CF 2 )-、-(C＝O)-O[(CF 2 ) 2 -O] n -(CF 2 )-(CF 2 )-、-(C＝O)-(CH 2 ) 2 -O-(CH 2 )-(CH 2 )-、-(C＝O)-(CF 2 ) 2 -O-(CF 2 )-(CF 2 )-、-(C＝O)-O-(CH 2 ) 2 -O-(CH 2 )-(CH 2 )-、-(C＝O)-O-(CF 2 ) 2 -O-(CF 2 )-(CF 2 )-、-(C＝O)-O-(CH 2 ) 2 -O-(CH 2 )-C(CF 3 ) 2 -、-(C＝O)-O-(CF 2 ) 2 -O-(CF 2 )-C(CF 3 ) 2 -, or- (c=o) -O-C 6 H 4 -C(CF 3 ) 2 -, more preferably-CF 2 -O-CF(CF 3 )-、-CF 2 -O-CF 2 -CF(CF 3 )-、-CF 2 -O-CF 2 CF 2 -CF(CF 3 )-、-CF 2 -O-CF(CF 3 )-CF(CF 3 )-、-CF 2 -O-CF(CF 3 )CF 2 -CF(CF 3 )-、-CF 2 -O-CF(CF 3 )CF 2 -O-CF(CF 3 )-、-(C＝O)-、-(C＝O)-O-(CH 2 )-、-(C＝O)-O-(CH 2 )-(CH 2 )-、-(C＝O)-O[(CH 2 ) 2 -O] n -(CH 2 )-(CH 2 )-、-(C＝O)-O-(CH 2 ) 2 -O-(CH 2 )-C(CF 3 ) 2 -, or- (c=o) -O-C 6 H 4 -C(CF 3 ) 2 -。
In the above formula, n is an integer of 1 to 10.
Specific examples of the compound represented by the general formula (4) include
[ chemical 19]
(wherein X is j And Y 3 The same as described above. n is an integer of 1 to 10), and the like.
As R a Preferably of formula (r 1):
-(C＝O) h -(O) i -CF 2 -O-(CX 6 2 ) e -{O-CF(CF 3 )} f -(O) g -(r1)
(wherein X is 6 Each independently is H, F or CF 3 E is an integer of 0 to 3, f is an integer of 0 to 3, g is 0 or 1, h is 0 or 1, i is 0 or 1) is a 2-valent group, also preferably of the formula (r 2):
-(C＝O) h -(O) i -CF 2 -O-(CX 7 2 ) e -(O) g -(r2)
(wherein X is 7 Each independently is H, F or CF 3 E is an integer of 0 to 3, g is 0 or 1, h is 0 or 1, and i is 0 or 1).
As-R of the formula (4) a -(CZ 1 Z 2 ) k Also preferred is the following formula (t 1):
-(C＝O) h -(O) i -CF 2 -O-(CX 6 2 ) e -{O-CF(CF 3 )} f -(O) g -CZ 1 Z 2 -(t1)
(wherein X is 6 Each independently is H, F or CF 3 E is an integer from 0 to 3, f is an integer from 0 to 3, g is 0 or 1, h is 0 or 1, i is 0 or 1, Z 1 And Z 2 Each independently is F or CF 3 ) A 2-valent group of the formula (t 1), Z 1 And Z 2 More preferably one is F and the other is CF 3 。
In addition, in the general formula (4)as-R a -(CZ 1 Z 2 ) k Also preferred is the following formula (t 2):
-(C＝O) h -(O) i -CF 2 -O-(CX 7 2 ) e -(O) g -CZ 1 Z 2 - (t2)
(wherein X is 7 Each independently is H, F or CF 3 E is an integer of 0 to 3, g is 0 or 1, h is 0 or 1, i is 0 or 1, Z 1 And Z 2 Each independently is F or CF 3 ) A 2-valent group of the formula (t 2), Z 1 And Z 2 More preferably one is F and the other is CF 3 。
The compound represented by the general formula (4) is also preferably a compound other than the hydrophilic group (Y 3 ) With the exception of C-F bonds and no C-H bonds. That is, in the general formula (4), X is preferable i 、X j And X k All are F, R a The Quan Fu alkylene group may be any of a chain type and a branched type, may be any of a cyclic type and an acyclic type, and may contain at least 1 chain hetero atom. The number of carbon atoms of the Quan Fu alkylene group may be 2 to 20 or 4 to 18.
The compounds of the general formula (4) may also be partially fluorinated. That is, the compound represented by the general formula (4) is also preferably a compound other than the hydrophilic group (Y 3 ) In addition to having at least 1 hydrogen atom bonded to a carbon atom, and having at least 1 fluorine atom bonded to a carbon atom.
The compound represented by the general formula (4) is also preferably a compound represented by the following formula (4 a).
CF 2 ＝CF-O-Rf 0 -Y 3 (4a)
(wherein Y is 3 As hydrophilic groups, rf 0 The perfluorinated divalent linking group may have a chain or branched, cyclic or acyclic structure, saturated or unsaturated, substituted or unsubstituted, and optionally contains 1 or more heteroatoms selected from the group consisting of sulfur, oxygen and nitrogen. )
The compound represented by the general formula (4) is also preferably a compound represented by the following formula (4 b).
CH 2 ＝CH-O-Rf 0 -Y 3 (4b)
(wherein Y is 3 As hydrophilic groups, rf 0 A perfluorinated divalent linking group defined for formula (4 a). )
In the general formula (4), Y 3 is-OSO 3 M is one of the preferred modes. Y is Y 3 is-OSO 3 In the case of M, examples of the compound represented by the general formula (4) include CF 2 ＝CF(OCF 2 CF 2 CH 2 OSO 3 M)、CH 2 ＝CH((CF 2 ) 4 CH 2 OSO 3 M)、CF 2 ＝CF(O(CF 2 ) 4 CH 2 OSO 3 M)、CF 2 ＝CF(OCF 2 CF(CF 3 )CH 2 OSO 3 M)、CF 2 ＝CF(OCF 2 CF(CF 3 )OCF 2 CF 2 CH 2 OSO 3 M)、CH 2 ＝CH((CF 2 ) 4 CH 2 OSO 3 M)、CF 2 ＝CF(OCF 2 CF 2 SO 2 N(CH 3 )CH 2 CH 2 OSO 3 M)、CH 2 ＝CH(CF 2 CF 2 CH 2 OSO 3 M)、CF 2 ＝CF(OCF 2 CF 2 CF 2 CF 2 SO 2 N(CH 3 )CH 2 CH 2 OSO 3 M), and the like. In the above formula, M is the same as described above.
In the general formula (4), Y 3 is-SO 3 M is also one of the preferred modes. Y is Y 3 is-SO 3 In the case of M, examples of the compound represented by the general formula (4) include CF 2 ＝CF(OCF 2 CF 2 SO 3 M)、CF 2 ＝CF(O(CF 2 ) 4 SO 3 M)、CF 2 ＝CF(OCF 2 CF(CF 3 )SO 3 M)、CF 2 ＝CF(OCF 2 CF(CF 3 )OCF 2 CF 2 SO 3 M)、CH 2 ＝CH(CF 2 CF 2 SO 3 M)、CF 2 ＝CF(OCF 2 CF(CF 3 )OCF 2 CF 2 CF 2 CF 2 SO 3 M)、CH 2 ＝CH((CF 2 ) 4 SO 3 M)、CH 2 ＝CH((CF 2 ) 3 SO 3 M), and the like. In the above formula, M is the same as described above.
In the general formula (4), Y 3 A-COOM is also one of the preferred modes. Y is Y 3 In the case of-COOM, CF is exemplified as the compound represented by the general formula (4) 2 ＝CF(OCF 2 CF 2 COOM)、CF 2 ＝CF(OCF 2 CF 2 CF 2 COOM)、CF 2 ＝CF(O(CF 2 ) 5 COOM)、CF 2 ＝CF(OCF 2 CF(CF 3 )COOM)、CF 2 ＝CF(OCF 2 CF(CF 3 )O(CF 2 ) n COOM) (n is greater than 1), CH 2 ＝CH(CF 2 CF 2 COOM)、CH 2 ＝CH((CF 2 ) 4 COOM)、CH 2 ＝CH((CF 2 ) 3 COOM)、CF 2 ＝CF(OCF 2 CF 2 SO 2 NR’CH 2 COOM)、CF 2 ＝CF(O(CF 2 ) 4 SO 2 NR’CH 2 COOM)、CF 2 ＝CF(OCF 2 CF(CF 3 )SO 2 NR’CH 2 COOM)、CF 2 ＝CF(OCF 2 CF(CF 3 )OCF 2 CF 2 SO 2 NR’CH 2 COOM)、CH 2 ＝CH(CF 2 CF 2 SO 2 NR’CH 2 COOM)、CF 2 ＝CF(OCF 2 CF(CF 3 )OCF 2 CF 2 CF 2 CF 2 SO 2 NR’CH 2 COOM)、CH 2 ＝CH((CF 2 ) 4 SO 2 NR’CH 2 COOM)、CH 2 ＝CH((CF 2 ) 3 SO 2 NR’CH 2 COOM), and the like. In the above formula, R' is H or C 1-4 Alkyl, M is the same as described above.
In the general formula (4), Y 3 is-OPO 3 M or-OP (O) (OM) 2 And is also one of the preferred modes. Y is Y 3 is-OPO 3 M or-OP (O) (OM) 2 In the case of (C), the compound represented by the general formula (4) may be CF 2 ＝CF(OCF 2 CF 2 CH 2 OP(O)(OM) 2 )、CF 2 ＝CF(O(CF 2 ) 4 CH 2 OP(O)(OM) 2 )、CF 2 ＝CF(OCF 2 CF(CF 3 )CH 2 OP(O)(OM) 2 )、CF 2 ＝CF(OCF 2 CF(CF 3 )OCF 2 CF 2 CH 2 OP(O)(OM) 2 )、CF 2 ＝CF(OCF 2 CF 2 SO 2 N(CH 3 )CH 2 CH 2 OP(O)(OM) 2 )、CF 2 ＝CF(OCF 2 CF 2 CF 2 CF 2 SO 2 N(CH 3 )CH 2 CH 2 OP(O)(OM) 2 )、CH 2 ＝CH(CF 2 CF 2 CH 2 OP(O)(OM) 2 、CH 2 ＝CH((CF 2 ) 4 CH 2 OP(O)(OM) 2 )、CH 2 ＝CH((CF 2 ) 3 CH 2 OP(O)(OM) 2 ) Etc. In the above formula, M is the same as described above.
In the general formula (4), Y 3 is-PO 3 M or-P (O) (OM) 2 And is also one of the preferred modes. Y is Y 3 is-PO 3 M or-P (O) (OM) 2 In the case of (C), the compound represented by the general formula (4) may be CF 2 ＝CF(OCF 2 CF 2 P(O)(OM) 2 )、CF 2 ＝CF(O(CF 2 ) 4 P(O)(OM) 2 )、CF 2 ＝CF(OCF 2 CF(CF 3 )P(O)(OM) 2 )、CF 2 ＝CF(OCF 2 CF(CF 3 )OCF 2 CF 2 P(O)(OM) 2 )、CH 2 ＝CH(CF 2 CF 2 P(O)(OM) 2 )、CH 2 ＝CH((CF 2 ) 4 P(O)(OM) 2 )、CH 2 ＝CH((CF 2 ) 3 P(O)(OM) 2 ) And the like, wherein M is the same as described above.
As the compound represented by the general formula (4), at least 1 selected from the group consisting of the following compounds represented by the general formula (5):
CX 2 ＝CY(-CZ 2 -O-Rf-Y 3 )(5)
(wherein X is the same or different and is-H or-F, Y is-H, -F, alkyl or fluoroalkyl, and Z is the same or different and is-H, -F, alkyl or fluoroalkyl Rf is a fluoroalkyl group having 1 to 40 carbon atoms or a fluoroalkylene group having 2 to 100 carbon atoms and having an ether bond 3 The same as above), a compound represented by the general formula (6):
CX 2 ＝CY(-O-Rf-Y 3 )(6)
(wherein X is the same or different and is-H or-F, Y is-H, -F, alkyl or fluoroalkyl, rf is a fluoroalkyl group having 1 to 40 carbon atoms or a fluoroalkylene group having 2 to 100 carbon atoms and having an ether bond 3 The same as above) of the compounds shown in the above; and general formula (7):
CX 2 ＝CY(-Rf-Y 3 )(7)
(wherein X is the same or different and is-H or-F, Y is-H, -F, alkyl or fluoroalkyl, rf is a fluoroalkyl group having 1 to 40 carbon atoms or a fluoroalkylene group having 2 to 100 carbon atoms and having an ether bond 3 The same as described above).
The above-mentioned fluorinated alkylene group having an ether bond having 2 to 100 carbon atoms is an alkylene group having an ether bond between carbon atoms and having a structure not including an oxygen atom as a terminal.
In the general formula (5), X is-H or-F. X may be either-F or-H. For example, one may be-F, the other may be-H, or both may be-H.
In the general formula (5), Y is-H, -F, alkyl or fluorine-containing alkyl.
The alkyl group is an alkyl group containing no fluorine atom, and the number of carbon atoms is 1 or more. The number of carbon atoms of the alkyl group is preferably 6 or less, more preferably 4 or less, and still more preferably 3 or less.
The fluoroalkyl group is an alkyl group having at least 1 fluorine atom, and the number of carbon atoms is 1 or more. The number of carbon atoms of the fluoroalkyl group is preferably 6 or less, more preferably 4 or less, and still more preferably 3 or less.
As the above Y, it is preferable that-H, -F or-CF 3 More preferably-F.
In the general formula (5), Z is the same or different and is-H, -F, alkyl or fluoroalkyl.
The alkyl group is an alkyl group containing no fluorine atom, and the number of carbon atoms is 1 or more. The number of carbon atoms of the alkyl group is preferably 6 or less, more preferably 4 or less, and still more preferably 3 or less.
The fluoroalkyl group is an alkyl group having at least 1 fluorine atom, and the number of carbon atoms is 1 or more. The number of carbon atoms of the fluoroalkyl group is preferably 6 or less, more preferably 4 or less, and still more preferably 3 or less.
As the above Z, it is preferable that-H, -F or-CF 3 More preferably-F.
In the general formula (5), at least one of the above X, Y and Z preferably contains a fluorine atom. For example, X is-H, Y and Z are-F.
In the general formula (5), rf is a fluorine-containing alkylene group having 1 to 40 carbon atoms or a fluorine-containing alkylene group having 2 to 100 carbon atoms and having an ether bond.
The number of carbon atoms of the above-mentioned fluorine-containing alkylene group is preferably 2 or more. The content is preferably 30 or less, more preferably 20 or less, and still more preferably 10 or less. As the above-mentioned fluorine-containing alkylene group, there may be mentioned-CF 2 -、-CH 2 CF 2 -、-CF 2 CF 2 -、-CF 2 CH 2 -、-CF 2 CF 2 CH 2 -、-CF(CF 3 )-、-CF(CF 3 )CF 2 -、-CF(CF 3 )CH 2 -and the like. The above-mentioned fluorinated alkylene group is preferably a perfluoroalkylene group.
The number of carbon atoms of the above-mentioned fluorine-containing alkylene group having an ether bond is preferably 3 or more. The number of carbon atoms of the fluorinated alkylene group having an ether bond is preferably 60 or less, more preferably 30 or less, and further preferably 12 or less.
As the fluorine-containing alkylene group having an ether bond, for example, the following formula is also preferable:
[ chemical 20]
(wherein Z is 1 Is F or CF 3 ；Z 2 And Z 3 H or F respectively; z is Z 4 H, F or CF 3 The method comprises the steps of carrying out a first treatment on the surface of the p1+q1+r1 is an integer of 1 to 10; s1 is 0 or 1; t1 is an integer of 0 to 5).
As the above-mentioned fluorine-containing alkylene group having an ether bond, specifically, there may be mentioned-CF (CF 3 )CF 2 -O-CF(CF 3 )-、-(CF(CF 3 )CF 2 -O) n -CF(CF 3 ) - (wherein n is an integer of 1 to 10), -CF (CF) 3 )CF 2 -O-CF(CF 3 )CH 2 -、-(CF(CF 3 )CF 2 -O) n -CF(CF 3 )CH 2 - (wherein n is an integer of 1 to 10), -CH 2 CF 2 CF 2 O-CH 2 CF 2 CH 2 -、-CF 2 CF 2 CF 2 O-CF 2 CF 2 -、-CF 2 CF 2 CF 2 O-CF 2 CF 2 CH 2 -、-CF 2 CF 2 O-CF 2 -、-CF 2 CF 2 O-CF 2 CH 2 -and the like. The above-mentioned fluorinated alkylene group having an ether bond is preferably a perfluoroalkylene group.
In the general formula (5), Y 3 preferably-COOM, -SO 3 M or-OSO 3 M (M is H, metal atom, NR) 7y 4 Imidazolium with or without substituents, pyridinium with or without substituents or phosphonium with or without substituents, R 7y H or an organic group may be the same or different. Any 2 may be bonded to each other to form a ring).
As R 7y The organic group in (2) is preferably an alkyl group.
As R 7y Preferably H or C 1-10 More preferably H or C 1-4 Further preferably H or C 1-4 Is a hydrocarbon group.
Examples of the metal atom include alkali metal (group 1) and alkaline earth metal (group 2), and Na, K, and Li are preferable.
As M, preference is given to-H, a metal atom or NR 7 4 More preferably-H, alkali metal (group 1), alkaline earth metal (group 2) or NR 7 4 Further preferred are-H, -Na, -K, -Li or NH 4 Further more preferably-H, -Na, -K or NH 4 Particularly preferred are-H, -Na or NH 4 Most preferably-H or-NH 4 。
As the above Y 3 preferably-COOM or-SO 3 M, more preferably-COOM.
The compound represented by the general formula (5) is preferably the compound (5 a) represented by the general formula (5 a).
CH 2 ＝CF(-CF 2 -O-Rf-Y 3 ) (5a)
(wherein Rf and Y 3 The same as described above. )
The compound represented by the general formula (5 a) is specifically represented by the following formula
[ chemical 21]
(wherein Z is 1 Is F or CF 3 ；Z 2 And Z 3 H or F respectively; z is Z 4 H, F or CF 3 The method comprises the steps of carrying out a first treatment on the surface of the p1+q1+r1 is an integer of 0 to 10; s1 is 0 or 1; t1 is an integer of 0 to 5, Y 3 The same as described above. Wherein Z is 3 And Z 4 All are H, p1+q1+r1+s1 is not 0). More specifically, preferable examples thereof include
[ chemical 22]
CH 2 ＝CFCF 2 OCH 2 CF 2 -y 3 ，CH 2 ＝CFCF 2 O(CH 2 CF 2 CF 2 O)CH 2 CF 2 -Y 3 ，
CH 2 ＝CFCF 2 OCH 2 CF 2 CH 2 -Y 3 ，
CH 2 ＝＝CFCF 2 O(CH 2 CF 2 CF 2 O)CH 2 CF 2 CH 2 -Y 3 ，
CH 2 ＝CFCF 2 OCF 2 CF 2 -Y 3 ，CH 2 ＝CFCF 2 O(CF 2 CF 2 CF 2 O)CF 2 CF 2 -Y 3 ，
CH 2 ＝CFCF 2 OCF 2 CF 2 CH 2 -Y 3 ，
CH 2 ＝CFCF 2 O(CF 2 CF 2 CF 2 O)CF 2 CF 2 CH 2 -Y 3 ，
CH 2 ＝CFCF 2 OCF 2 -Y 3 ，CH 2 ＝CFCF 2 O(CF 2 CF 2 O)CF 2 -Y 3 ，
CH 2 ＝CFCF 2 OCF 2 CH 2 -Y 3 ，
CH 2 ＝CFCF 2 O(CF 2 CF 2 O)CF 2 CH 2 -Y 3 ，
Etc., of which preference is given to
[ chemical 23]
As the compound represented by the general formula (5 a), Y in the general formula (5 a) is preferable 3 is-COOM, particularly preferably selected from CH 2 ＝CFCF 2 OCF(CF 3 ) COOM and CH 2 ＝CFCF 2 OCF(CF 3 )CF 2 OCF(CF 3 ) COOM (wherein M is as defined above), more preferably CH 2 ＝CFCF 2 OCF(CF 3 )COOM。
The compound represented by the general formula (5) is preferably the compound (5 b) represented by the general formula (5 b).
CX 2 2 ＝CFCF 2 -O-(CF(CF 3 )CF 2 O) n5 -CF(CF 3 )-Y 3 (5b)
(wherein each X 2 And the same, represents F or H. n5 represents 0 or an integer of 1 to 10, Y 3 The same definition as above. )
In the formula (5 b), from the viewpoint of stability of the aqueous dispersion obtained, n5 is preferably 0 or an integer of 1 to 5, more preferably 0, 1 or 2, and even more preferably 0 or 1. From the viewpoint of obtaining moderate water solubility and stability of aqueous dispersion, Y is 3 preferably-COOM, wherein M is preferably H or NH, in view of the difficulty in remaining as an impurity and the improvement of heat resistance of the obtained molded article 4 。
Examples of the compound represented by the above formula (5 b) include CH 2 ＝CFCF 2 OCF(CF 3 )COOM、CH 2 ＝CFCF 2 OCF(CF 3 )CF 2 OCF(CF 3 ) COOM (wherein M is as defined above).
The compound represented by the general formula (5) may be a compound represented by the general formula (5 c).
CF 2 ＝CFCF 2 -O-Rf-Y 3 (5c)
(wherein Rf and Y 3 The same as described above. )
More specifically, there may be mentioned
[ chemical 24]
CF 2 ＝CFCF 2 OCF 2 CF 2 CF 2 -Y 3 ，
CF 2 ＝CFCF 2 OCF 2 CF 2 CF 2 CH 2 -Y 3 ，
Etc.
In the general formula (6), X is-H or-F. X may be either-F or-H. For example, one may be-F, the other may be-H, or both may be-H.
In the general formula (6), Y is-H, -F, alkyl or fluoroalkyl.
The alkyl group is an alkyl group containing no fluorine atom, and the number of carbon atoms is 1 or more. The number of carbon atoms of the alkyl group is preferably 6 or less, more preferably 4 or less, and still more preferably 3 or less.
The fluoroalkyl group is an alkyl group having at least 1 fluorine atom, and the number of carbon atoms is 1 or more. The number of carbon atoms of the fluoroalkyl group is preferably 6 or less, more preferably 4 or less, and still more preferably 3 or less.
As the above Y, it is preferable that-H, -F or-CF 3 More preferably-F.
In the general formula (6), at least one of the above X and Y preferably contains a fluorine atom. For example, X is-H, Y and Z are-F.
In the general formula (6), rf is a fluorine-containing alkylene group having 1 to 40 carbon atoms or a fluorine-containing alkylene group having 2 to 100 carbon atoms and having an ether bond.
The number of carbon atoms of the above-mentioned fluorine-containing alkylene group is preferably 2 or more. The number of carbon atoms of the fluorinated alkylene group is preferably 30 or less, more preferably 20 or less, and further preferably 10 or less. As the above-mentioned fluorine-containing alkylene group, there may be mentioned-CF 2 -、-CH 2 CF 2 -、-CF 2 CF 2 -、-CF 2 CH 2 -、-CF 2 CF 2 CH 2 -、-CF(CF 3 )-、-CF(CF 3 )CF 2 -、-CF(CF 3 )CH 2 -and the like. The above-mentioned fluorinated alkylene group is preferably a perfluoroalkylene group.
In the above general formula (6), Y 3 preferably-COOM, -SO 3 M or-OSO 3 M (M is H, metal atom, NR) 7y 4 Imidazolium with or without substituents, pyridinium with or without substituents or phosphonium with or without substituents, R 7y H or an organic group may be the same or different.Any 2 may be bonded to each other to form a ring).
As R 7y Preferably alkyl. As R 7y Preferably H or C 1-10 More preferably H or C 1-4 Further preferably H or C 1-4 Is a hydrocarbon group.
Examples of the metal atom include alkali metal (group 1) and alkaline earth metal (group 2), and Na, K, and Li are preferable.
As M, preference is given to-H, a metal atom or NR 7 4 More preferably-H, alkali metal (group 1), alkaline earth metal (group 2) or NR 7 4 Further preferred are-H, -Na, -K, -Li or NH 4 Further more preferably-H, -Na, -K or NH 4 Particularly preferred are-H, -Na or NH 4 Most preferably-H or-NH 4 。
As the above Y 3 preferably-COOM or-SO 3 M。
The compound represented by the general formula (6) is preferably at least 1 selected from the group consisting of compounds represented by the general formulae (6 a), (6 b), (6 c), (6 d) and (6 e).
CF 2 ＝CF-O-(CF 2 ) n1 -Y 3 (6a)
(wherein n1 represents an integer of 1 to 10, Y) 3 The same definition as above. )
CF 2 ＝CF-O-(CF 2 C(CF 3 )F) n2 -Y 3 (6b)
(wherein n2 represents an integer of 1 to 5, Y) 3 The same definition as above. )
CF 2 ＝CF-O-(CFX 1 ) n3 -Y 3 (6c)
(wherein X is 1 Represents F or CF 3 N3 represents an integer of 1 to 10, Y 3 The same definition as above. )
CF 2 ＝CF-O-(CF 2 CFX 1 O) n4 -(CF 2 ) n6 -Y 3 (6d)
(wherein n4 represents an integer of 1 to 10, n6 represents an integer of 1 to 3, Y 3 And X 1 And above-mentionedThe definitions are the same. )
CF 2 ＝CF-O-(CF 2 CF 2 CFX 1 O) n5 -CF 2 CF 2 CF 2 -Y 3 (6e)
(wherein n5 represents an integer of 0 to 10, Y) 3 And X 1 The same definition as above. )
In the formula (6 a), n1 is preferably an integer of 5 or less, more preferably an integer of 2 or less. From the viewpoint of obtaining moderate water solubility and stability of aqueous dispersion, Y is 3 preferably-COOM or-SO 3 M is preferably H or NH in view of the difficulty in remaining as an impurity and the improvement in heat resistance of the molded article obtained 4 。
Examples of the compound represented by the above formula (6 a) include CF 2 ＝CF-O-CF 2 COOM、CF 2 ＝CF(OCF 2 CF 2 COOM)、CF 2 ＝CF(OCF 2 CF 2 CF 2 COOM)、CF 2 ＝CF-O-CF 2 SO 3 M、CF 2 ＝CF(OCF 2 CF 2 SO 3 M)、CF 2 ＝CF(OCF 2 CF 2 CF 2 SO 3 M) (where M is as defined above).
In the above formula (6 b), from the viewpoint of stability of the aqueous dispersion obtained, n2 is preferably an integer of 3 or less, and from the viewpoint of obtaining moderate water solubility and stability of the aqueous dispersion, Y 3 preferably-COOM or-SO 3 M is preferably H or NH in view of the difficulty in remaining as an impurity and the improvement in heat resistance of the molded article obtained 4 。
In the above formula (6 c), n3 is preferably an integer of 5 or less in terms of water solubility, and Y is preferably an integer of 5 or less in terms of obtaining proper water solubility and stability of an aqueous dispersion 3 preferably-COOM or-SO 3 M is preferably H or NH from the viewpoint of improving dispersion stability 4 。
In the above formula (6 d), X is as described above in terms of stability of the aqueous dispersion 1 Preferably is-CF 3 From the viewpoint of water solubility, n4 is preferably an integer of 5 or less, and from the viewpoint of obtaining moderate water solubility and stability of the aqueous dispersion, Y is preferably 3 preferably-COOM or-SO 3 M, where M is preferably H or NH 4 。
Examples of the compound represented by the above formula (6 d) include CF 2 ＝CFOCF 2 CF(CF 3 )OCF 2 CF 2 COOM、CF 2 ＝CFOCF 2 CF(CF 3 )OCF 2 COOM、CF 2 ＝CFOCF 2 CF(CF 3 )OCF 2 CF 2 CF 2 COOM、CF 2 ＝CFOCF 2 CF(CF 3 )OCF 2 CF 2 SO 3 M、CF 2 ＝CFOCF 2 CF(CF 3 )OCF 2 SO 3 M、CF 2 ＝CFOCF 2 CF(CF 3 )OCF 2 CF 2 CF 2 SO 3 M (where M represents H, NH) 4 Or an alkali metal).
In the general formula (6 e), n5 is preferably an integer of 5 or less in terms of water solubility, and Y is preferably an integer of 5 or less in terms of obtaining moderate water solubility and stability of the aqueous dispersion 3 preferably-COOM or-SO 3 M, where M is preferably H or NH 4 。
Examples of the compound represented by the general formula (6 e) include CF 2 ＝CFOCF 2 CF 2 CF 2 COOM、CF 2 ＝CFOCF 2 CF 2 CF 2 SO 3 M (where M represents H, NH) 4 Or an alkali metal).
In the general formula (7), rf is preferably a fluorine-containing alkylene group having 1 to 40 carbon atoms. In the general formula (7), at least one of X and Y preferably contains a fluorine atom.
The compound represented by the general formula (7) is preferably selected from the compounds represented by the general formula (7 a):
CF 2 ＝CF-(CF 2 ) n1 -Y 3 (7a)
(wherein n1 represents an integer of 1 to 10, Y) 3 The same as defined above), and a compound represented by the general formula (7 b):
CF 2 ＝CF-(CF 2 C(CF 3 )F) n2 -Y 3 (7b)
(wherein n2 represents an integer of 1 to 5, Y) 3 The same as defined above) at least 1 of the group consisting of the compounds shown.
Above Y 3 preferably-SO 3 M or-COOM, M is preferably H, a metal atom, NR 7y 4 An imidazolium with or without substituents, a pyridinium with or without substituents, or a phosphonium with or without substituents. R is as described above 7y Represents H or an organic group.
In the formula (7 a), n1 is preferably an integer of 5 or less, more preferably an integer of 2 or less. From the viewpoint of obtaining moderate water solubility and stability of aqueous dispersion, Y is 3 preferably-COOM or-SO 3 M is preferably H or NH in view of the difficulty in remaining as an impurity and the improvement in heat resistance of the molded article obtained 4 。
Examples of the compound represented by the above formula (7 a) include CF 2 ＝CFCF 2 COOM、CF 2 ＝CFCF 2 SO 3 M (wherein M is as defined above).
In the above formula (7 b), from the viewpoint of stability of the aqueous dispersion obtained, n2 is preferably an integer of 3 or less, and from the viewpoint of obtaining moderate water solubility and stability of the aqueous dispersion, Y 3 preferably-COOM or-SO 3 M is preferably H or NH in view of the difficulty in remaining as an impurity and the improvement in heat resistance of the molded article obtained 4 。
The above-mentioned modifying monomer preferably contains the modifying monomer (a), preferably contains at least 1 selected from the group consisting of the compounds represented by the general formula (5 a), the general formula (5 c), the general formula (6 a), the general formula (6 b), the general formula (6 c) and the general formula (6 d), and more preferably contains the compound represented by the general formula (5 a) or the general formula (5 c).
When the modifying monomer (a) is used as the modifying monomer, the content of the modifying monomer (a) unit is preferably in the range of 0.00001 to 1.0 mass% relative to the total polymerized units of the TFE Polymer (PTFE). The lower limit is more preferably 0.0001 mass%, still more preferably 0.0005 mass%, still more preferably 0.001 mass%, still more preferably 0.005 mass%. The upper limit is preferably 0.90 mass%, 0.50 mass%, 0.40 mass%, 0.30 mass%, 0.20 mass%, 0.15 mass%, 0.10 mass%, 0.08 mass%, 0.05 mass%, or 0.01 mass%.
In the production of the TFE polymer, the polymer (1) can be used within the range of use in the production method of the present invention. The concentration of the polymer (1) is not particularly limited as long as it is within the above range. If the amount of the additive is too large, needle-like particles having a large aspect ratio are formed, and the aqueous dispersion may be in a gel form and the stability may be impaired. The lower limit of the amount of the polymer (1) to be used is preferably 0.0001% by mass, more preferably 0.001% by mass, still more preferably 0.01% by mass, particularly preferably 0.02% by mass, relative to the aqueous medium. The upper limit of the amount of the polymer (1) to be used is preferably 10% by mass, more preferably 5% by mass, relative to the aqueous medium.
The polymer (1) may be added to the reaction vessel at once before the start of polymerization, may be added at once after the start of polymerization, may be added in several portions during polymerization, or may be added continuously during polymerization.
In the production of the TFE polymer, an organic peroxide such as persulfate (e.g., ammonium persulfate), disuccinate peroxide, and dipentaerythritol peroxide may be used alone or as a mixture of these. Alternatively, the catalyst may be used in combination with a reducing agent such as sodium sulfite to prepare a redox system. Further, a radical scavenger such as hydroquinone or catechol, or a decomposition agent such as a peroxide such as ammonium sulfite may be added to adjust the radical concentration in the system during the polymerization.
As the polymerization initiator of the above redox system, a redox initiator in which an oxidizing agent is combined with a reducing agent is preferably used. Examples of the oxidizing agent include persulfates, organic peroxides, potassium permanganate, manganese triacetate, and ammonium cerium nitrate. Examples of the reducing agent include sulfite, bisulfite, bromate, diimine, and oxalic acid. Examples of the persulfate include ammonium persulfate and potassium persulfate. The sulfite may be sodium sulfite or ammonium sulfite. In order to increase the decomposition rate of the initiator, it is also preferable to add a copper salt or an iron salt to the combination of redox initiators. Copper salts include copper (II) sulfate, and iron salts Include Iron (II) sulfate.
Examples of the redox initiator include potassium permanganate/oxalic acid, ammonium persulfate/bisulfite/ferric sulfate, manganese triacetate/oxalic acid, ceric ammonium nitrate/oxalic acid, bromate/bisulfite, and the like, and potassium permanganate/oxalic acid is preferable. In the case of using a redox initiator, either one of the oxidizing agent and the reducing agent may be charged into the polymerization vessel in advance, and then the other may be continuously or intermittently added to initiate polymerization. For example, in the case of using potassium permanganate/oxalic acid, it is preferable to charge oxalic acid into a polymerization vessel and continuously add potassium permanganate thereto.
In the production of the TFE polymer, a known chain transfer agent may be used, and examples thereof include saturated hydrocarbons such as methane, ethane, propane, and butane, halogenated hydrocarbons such as methyl chloride, methylene chloride, and difluoroethane, alcohols such as methanol, ethanol, and isopropanol, and hydrogen, and the like, and preferably the chain transfer agent is in a gaseous state at normal temperature and pressure.
The amount of the chain transfer agent is usually 1 to 10000 mass ppm, preferably 1 to 5000 mass ppm, based on the total amount of TFE to be supplied.
In the production of the TFE polymer, a saturated hydrocarbon having 12 or more carbon atoms, which is substantially inert in the reaction and is liquid under the reaction conditions, may be used as a dispersion stabilizer for the reaction system in an amount of 2 to 10 parts by mass based on 100 parts by mass of the aqueous medium. In addition, as a buffer for adjusting the pH in the reaction, ammonium carbonate, ammonium phosphate, or the like may be added.
At the time of termination of the polymerization of TFE, a polymerization dispersion having a solid content concentration of 1.0 to 50% by mass and an average primary particle diameter of 50 to 500nm can be obtained.
The lower limit of the solid content concentration is preferably 5% by mass, more preferably 8% by mass. The upper limit is not particularly limited, and may be 40% by mass or 35% by mass.
The lower limit of the average primary particle diameter is preferably 100nm, more preferably 150nm. The upper limit is preferably 400nm, more preferably 350nm.
The average primary particle diameter can be measured by a dynamic light scattering method. The average primary particle diameter was adjusted to a solid content concentration of about 1.0 mass% to prepare an aqueous dispersion, and the dispersion was measured by a dynamic light scattering method under conditions of 25℃and a solvent (water) refractive index of 1.3328, a solvent (water) viscosity of 0.8878 mPas, and 70 times total. As the dynamic light scattering method, for example, ELSZ-1000S (manufactured by Otsuka electronics Co., ltd.) can be used.
The average primary particle diameter can be determined by measuring the transmittance of 550nm projected light per unit length of the aqueous dispersion in which the solid content concentration is adjusted to 0.15 mass%, and the number-basis length average primary particle diameter determined by measuring the orientation diameter by a transmission electron micrograph, and by preparing a calibration curve using the calibration curve, the measured transmittance of 550nm projected light of each sample is determined.
The fine powder may be produced by precipitation of an aqueous dispersion of TFE polymer. The aqueous dispersion of TFE polymer can be precipitated, washed, dried and used in the form of a fine powder for various applications. In the case of precipitating the aqueous dispersion of the TFE polymer, usually, the aqueous dispersion obtained by polymerization such as a polymer emulsion is diluted with water to a polymer concentration of 5 to 20 mass%, and if necessary, the aqueous dispersion is stirred more vigorously than the stirring during the reaction in a vessel equipped with a stirrer after the pH is adjusted to neutral or alkaline. In the above-mentioned precipitation, a water-soluble organic compound such as methanol or acetone, an inorganic salt such as potassium nitrate or ammonium carbonate, an inorganic acid such as hydrochloric acid, sulfuric acid or nitric acid, or the like may be added as a precipitating agent while stirring. The above-mentioned precipitation may be carried out continuously using a pipe mixer or the like.
From the viewpoint of productivity, the concentration of the non-coagulated TFE polymer in the wastewater generated by the coagulation is preferably low, more preferably less than 0.4 mass%, and particularly preferably less than 0.3 mass%.
Before or during the above-mentioned precipitation, pigment or filler-containing TFE polymer fine powder uniformly mixed with pigment or filler can be obtained by adding pigment for coloring or various fillers for improving mechanical properties.
The wet powder obtained by precipitating the aqueous dispersion of the TFE polymer is usually dried by vacuum, high frequency, hot air, or the like while keeping the wet powder in a state of hardly flowing, preferably in a state of standing. Friction between powders, especially at high temperatures, typically has an adverse effect on the fine powder TFE polymer. This is because such particles made of TFE polymer have a property that they are easily fibrillated even when subjected to a small shearing force, and lose the state of an originally stable particle structure.
The drying is carried out at a drying temperature of 10 to 300 ℃, preferably 100 to 300 ℃.
The TFE polymer in the aqueous dispersion may be precipitated by using an acid having no metal element, or may be stirred to precipitate, and the precipitated TFE polymer may be washed with a liquid medium having a reduced content of metal element. The washed TFE polymer may be further dried. By such a production method, a TFE polymer having a metal content of 10 mass ppm or less in the TFE polymer can be produced. As the liquid medium, water is preferable, and ultrapure water is more preferable. The metal content of the liquid medium is preferably 2 mass ppm or less, more preferably 1 mass ppm or less, and still more preferably 0.5 mass ppm or less.
The TFE polymer fine powder thus obtained is preferably used for molding, and examples of suitable applications include hydraulic systems for aircrafts, automobiles, etc., pipes for fuel systems, etc., flexible hoses for reagents, vapors, etc., and wire coating applications.
The aqueous dispersion of TFE polymer is preferably stabilized by adding a nonionic surfactant, and further concentrated, and an organic or inorganic filler is added according to the purpose to prepare a composition for various applications. The composition can be coated on a substrate made of metal or ceramic to form a coating film surface having non-tackiness, low friction coefficient, gloss, smoothness, abrasion resistance, weather resistance and heat resistance, and is suitable for coating of rolls, cooking devices and the like, impregnating processing of glass cloth and the like.
Organosols of TFE polymers can also be prepared from the above aqueous dispersions. The organosol may contain the TFE polymer and an organic solvent, and examples of the organic solvent include an ether solvent, a ketone solvent, an alcohol solvent, an amide solvent, an ester solvent, an aliphatic hydrocarbon solvent, an aromatic hydrocarbon solvent, and a halogenated hydrocarbon solvent, and N-methyl-2-pyrrolidone, dimethylacetamide, and the like can be suitably used. The preparation of the organosol can be carried out, for example, by the method described in International publication No. 2012/002038.
The aqueous dispersion of the TFE polymer or the TFE polymer fine powder is also preferably used as a processing aid. When the aqueous dispersion or the fine powder is used as a processing aid, the melt strength of the host polymer at the time of melt processing can be improved by mixing the aqueous dispersion or the fine powder with the host polymer, and the mechanical strength, electrical characteristics, flame retardancy, anti-dripping property at the time of combustion, and slidability of the obtained polymer can be improved.
The aqueous dispersion of the TFE polymer or the TFE polymer fine powder is preferably used as a battery binder or a dustproof purpose.
The aqueous dispersion of the TFE polymer or the TFE polymer fine powder is preferably compounded with a resin other than TFE polymer and then used as a processing aid. The aqueous dispersion or the fine powder is suitable as a raw material of PTFE described in, for example, JP-A-11-49912, U.S. Pat. No. 5804654, JP-A-11-29679, and JP-A-2003-2980. The processing aid using the above aqueous dispersion or the above fine powder is also equivalent to the processing aid described in each of the above publications.
The aqueous dispersion of TFE polymer is also preferably prepared as a coprecipitated powder by mixing with an aqueous dispersion of melt-processible fluororesin and precipitating. The coprecipitated powder is suitable as a processing aid.
Examples of the melt-processible fluororesin include FEP, PFA, TFE/perfluoroallyl ether copolymer, ETFE, ethylene/TFE/HFP copolymer [ EFEP ], and the like, and PFA or FEP is preferable.
The aqueous dispersion preferably further contains the melt-processible fluororesin. Examples of the melt-processible fluororesin include FEP, PFA, TFE/perfluoroallyl ether copolymer, ETFE, EFEP, and the like. The aqueous dispersion containing the melt-processible fluororesin may be used as a coating material. The melt-processible fluororesin can sufficiently weld particles of the TFE polymer to each other, and thus can improve film forming properties and make the obtained film glossy.
The non-fluorine-containing resin to which the coprecipitated powder is added may be in the form of powder, granule, or emulsion. From the viewpoint of sufficiently mixing the resins, it is preferable to add the resins while applying a shearing force by a known method such as extrusion kneading or roll kneading.
The aqueous dispersion of TFE polymer is preferably used as a dust suppression agent. The dust suppression agent may be used in the following method: a method of mixing the mixture with a dust-forming substance and applying a compression-shearing action to the mixture at a temperature of 20 to 200 ℃ to fibrillate a TFE polymer to thereby inhibit dust of the dust-forming substance; for example, japanese patent publication No. 2827152 and Japanese patent publication No. 2538783.
The aqueous dispersion of the TFE polymer can be suitably used in, for example, a dust suppression treatment agent composition described in international publication No. 2007/004250, and can also be suitably used in a dust suppression treatment method described in international publication No. 2007/000812.
The dust-suppressing agent is suitable for dust-suppressing treatment of sand for pet excretion represented by cat litter, etc. in the field of building materials, the field of soil stabilizer, the field of solidified materials, the field of fertilizer, the field of leveling treatment of incineration ash and harmful substances, the field of explosion protection, the field of cosmetics, and the field of cat litter.
The aqueous dispersion of the TFE polymer is preferably used as a raw material for obtaining TFE polymer fibers by a dispersion spinning method (Dispersion Spinning method). The dispersion spinning method is the following method: the aqueous dispersion of the TFE polymer is mixed with the aqueous dispersion of the matrix polymer, the mixture is extruded to form an intermediate fiber structure, and the intermediate fiber structure is fired, whereby the matrix polymer is decomposed and the TFE polymer particles are sintered to obtain TFE polymer fibers.
The high molecular weight PTFE powder obtained by polymerization has stretchability and non-melt processability, and is also useful as a raw material for a stretched body (porous body).
In the case where the stretched body is a film (PTFE stretched film or PTFE porous film), stretching can be performed by a known PTFE stretching method. By stretching, the high molecular weight PTFE is easily fibrillated to form a porous PTFE body (film) composed of nodules and fibers.
The sheet-like or rod-like paste extrudate is preferably roll-stretched in the extrusion direction, whereby a uniaxially stretched film can be obtained.
Further, a biaxially stretched film can be obtained by stretching in the width direction by a tenter or the like.
It is also preferable to perform the half-baking treatment before stretching.
The PTFE stretched body is a porous body having a high porosity, and can be suitably used as a filter material for various microfiltration filters such as an air filter and a reagent filter, a support material for a polymer electrolyte membrane, and the like.
The material is also useful as a product used in the fields of fiber, medical treatment, electrochemistry, sealing material, air filtration, ventilation/internal pressure adjustment, liquid filtration, general consumption materials, and the like.
Specific uses are exemplified below.
Electrochemical field
A dielectric material prepreg, an EMI shielding material, a heat transfer material, and the like. More specifically, a printed circuit board, an electromagnetic shielding material, an insulating heat transfer material, an insulating material, and the like.
Sealing material field
Gaskets, seals, pump diaphragms, pump tubes, aircraft seals, and the like.
Air filtration field
ULPA filters (for semiconductor manufacturing), HEPA filters (for hospital and semiconductor manufacturing), cylindrical cartridge filters (for industrial use), bag filters (for industrial use), heat-resistant bag filters (for exhaust gas treatment), heat-resistant pleated filters (for exhaust gas treatment), SINBRAN filters (for industrial use), catalytic filters (for exhaust gas treatment), filters with adsorbents (HDD assembly), breather filters (for HDD assembly, etc.), dust collector filters (for dust collectors), universal multi-layer felt, GT cartridge filters (for interchangeable products suitable for GT), cooling filters (for electronic equipment housings), and the like.
Air exchange/internal pressure regulation field
A freeze-drying material for a freeze-drying container or the like, an automotive ventilation material suitable for an electronic circuit or a lamp, a container use suitable for a container cover or the like, a protective ventilation use suitable for an electronic device or the like including a small-sized terminal such as an input panel terminal or a mobile phone terminal, a medical ventilation use, or the like.
Liquid filtration field
Semiconductor liquid filters (for semiconductor production), hydrophilic PTFE filters (for semiconductor production), filters suitable for chemicals (for reagent treatment), filters for pure water production lines (for pure water production), backwash type liquid filter filters (for industrial wastewater treatment), and the like.
General consumable Material field
Garments, cable guides (movable wires suitable for motorcycles), garments for motorcycles, casting pads (medical protective gear), dust collector filters, whistles (musical instruments), cables (guitar signal cables, etc.), strings (string instruments), etc.
Fiber field
PTFE fibers (fibrous material), sewing threads (fabric), knitting threads (fabric), ropes, etc.
Medical field
In vivo implants (stretch products), vascular prostheses, catheters, general surgery (tissue reinforcement), head and neck products (dura substitute), intraoral health (tissue regeneration medical treatment), orthopedic surgery (tape), etc.
By the production method of the present invention, low-molecular-weight PTFE can also be produced.
The low-molecular-weight PTFE may be produced by polymerization, or the high-molecular-weight PTFE obtained by polymerization may be produced by subjecting it to low-molecular weight by a known method (thermal decomposition, radiation decomposition, etc.).
Since low molecular weight PTFE (also referred to as PTFE fine powder) having a molecular weight of 60 ten thousand or less is excellent in chemical stability, extremely low in surface energy, and less susceptible to fibrillation, it is suitable as an additive for improving slidability, texture of a coating film surface, and the like, for the production of plastics, inks, cosmetics, paints, greases, office automation equipment parts, toners, and the like (for example, see japanese patent application laid-open No. 10-147617).
Further, the polymerization initiator and the polymer (1) may be dispersed in an aqueous medium in the presence of a chain transfer agent, and TFE, or a monomer copolymerizable with TFE and TFE may be polymerized to obtain a low molecular weight PTFE. In this case, the chain transfer agent is preferably at least 1 selected from the group consisting of alkanes having 2 to 4 carbon atoms. Specifically, methane, ethane, propane, butane, and isobutane are more preferable, and ethane and propane are still more preferable. In this case, the amount of the chain transfer agent is preferably 10 mass ppm or more than 10 mass ppm with respect to the aqueous medium.
When the low molecular weight PTFE obtained by the polymerization is used as a powder, the aqueous dispersion may be precipitated to prepare powder particles.
In the present invention, the high molecular weight PTFE preferably has non-melt processability and fibrillation. On the other hand, the low molecular weight PTFE preferably has melt processability and does not have fibrillation.
The above non-melt processability refers to the property that the melt flow rate cannot be measured at a temperature higher than the crystallization melting point according to ASTM D1238 and D2116.
The presence or absence of fibrillation can be determined by "paste extrusion", which is a typical method of molding a powder made of a polymer of TFE, that is, "high molecular weight PTFE powder". This is because, in general, PTFE having a high molecular weight has fibrillation properties when paste extrusion is possible. When the unfired molded article obtained by paste extrusion does not have substantial strength or elongation, for example, when the elongation is 0% and the molded article breaks when stretched, it is considered that the molded article does not have fibrillation.
The Standard Specific Gravity (SSG) of the high molecular weight PTFE is preferably 2.130 to 2.280. The standard specific gravity was measured by the substitution method in water according to ASTM D792 using a sample molded according to ASTM D4895-89. In the present invention, "high molecular weight" means that the above standard specific gravity is within the above range.
The melt viscosity of the low molecular weight PTFE at 380 ℃ is 1X 10 2 Pa·s～7×10 5 Pa·s. In the present invention, "low molecular weight" means that the melt viscosity falls within the above range. The melt viscosity was the following value: according to ASTM D1238, a flow tester (manufactured by Shimadzu corporation) andthe melt viscosity was measured by keeping a 2g sample heated at 380℃for 5 minutes at the above temperature under a load of 0.7 MPa.
The high-molecular-weight PTFE has a very high melt viscosity compared with the low-molecular-weight PTFE, and it is difficult to measure the exact melt viscosity. On the other hand, although the melt viscosity of the low-molecular-weight PTFE can be measured, it is difficult to obtain a molded article usable for measurement of standard specific gravity from the low-molecular-weight PTFE, and it is difficult to measure the accurate standard specific gravity. In the present invention, therefore, the standard specific gravity is used as an index of the molecular weight of the high-molecular-weight PTFE, and the melt viscosity is used as an index of the molecular weight of the low-molecular-weight PTFE. In the case of the high molecular weight PTFE and the low molecular weight PTFE, a method for measuring a molecular weight which can be directly specified is not known.
The peak temperature of the high molecular weight PTFE is preferably 333 to 347℃and more preferably 335 to 345 ℃. The peak temperature of the low molecular weight PTFE is preferably 322 to 333 ℃, more preferably 324 to 332 ℃. The peak temperature may be specified by heating PTFE which has not been heated to a temperature of 300℃or higher at 10℃per minute using TG/DTA (differential thermal gravimetric measuring instrument), and the temperature may be specified to a temperature corresponding to the maximum value appearing in the Differential Thermal (DTA) curve obtained by this.
The peak temperature of PTFE may be 322℃to 347 ℃.
The upper limit of the peak temperature of PTFE when PTFE is a high molecular weight PTFE may be 347℃or lower, 346℃or lower, 345℃or lower, 344℃or lower, 343℃or lower, 342℃or lower, 341℃or lower, 340℃or lower.
The lower limit of the peak temperature of PTFE when PTFE is high molecular weight PTFE may be 333 ℃ or higher and 335 ℃ or higher.
The upper limit of the peak temperature of PTFE when PTFE is low molecular weight PTFE may be 333 ℃ or lower and 332 ℃ or lower.
The lower limit of the peak temperature of PTFE when PTFE is low molecular weight PTFE may be 322 ℃ or higher and 324 ℃ or higher.
The average primary particle diameter of the primary particles of the low-molecular-weight PTFE is preferably 10nm to 200nm, more preferably 20nm to 150nm, still more preferably 140nm to 90 nm. The relatively small average primary particle diameter of the primary particles can be obtained, for example, by adding a modifying monomer to the polymerization system at the initial stage of polymerization of TFE.
The average primary particle diameter of the primary particles of the low molecular weight PTFE can be measured by a dynamic light scattering method. First, an aqueous dispersion of low-molecular-weight PTFE having a polymer solid content of about 1.0 mass% was prepared, and the dispersion was measured by a dynamic light scattering method, with a measurement temperature of 25 ℃, a refractive index of a solvent (water) of 1.3328, a viscosity of the solvent (water) of 0.8878mpa·s, and the number of times of accumulation of the dispersion of the solvent (water) of 70 times. For example, ELSZ-1000S (manufactured by Otsuka electronics Co., ltd.) can be used for the dynamic light scattering method.
The high molecular weight PTFE is preferably one which has not been heated to a temperature of 300 ℃ or higher, and which has a melting heat curve obtained by heating PTFE at a temperature of 10 ℃/min using a differential scanning calorimeter [ DSC ] and which has at least 1 or more endothermic peak in a range of 333 to 347 ℃ and which has a melting heat of 52mJ/mg or higher at 290 to 350 ℃ calculated from the melting heat curve. The heat of fusion of PTFE is more preferably 55mJ/mg or more, still more preferably 58mJ/mg or more.
The PTFE fine powder obtained as described above can also give an unfired tape (green tape).
(II) melt-processible fluororesin
In the production method 1 of the present invention, a melt-processible fluororesin such as a TFE/HFP copolymer [ FEP ], a TFE/perfluoro (alkyl vinyl ether) copolymer [ PFA, MFA, etc. ], a TFE/perfluoro (alkyl allyl ether) copolymer, or an electrolyte polymer precursor can be produced as a fluorine-containing polymer by polymerizing a perfluoro monomer such as TFE.
(1) In the production method of the present invention, the polymerization of FEP is preferably carried out at a polymerization temperature of 10 to 150℃and a polymerization pressure of 0.3MPaG to 6.0 MPaG.
The preferred monomer composition (mass%) of FEP is TFE: hfp= (60 to 95): (5 to 40), more preferably (85 to 92): (8-15).
In addition to TFE and HFP, other monomers copolymerizable with these monomers may be polymerized to thereby obtain a copolymer of TFE, HFP and other monomers as FEP. As other monomers, the above-mentioned fluoromonomers (excluding TFE and HFP) and non-fluoromonomers are exemplified. As the other monomer, 1 or more kinds may be used. As the other monomer, perfluoro (alkyl vinyl ether) is preferable. The content of the other monomer units in the FEP may be 0.1 to 2 mass% with respect to the total monomer units.
In the polymerization of FEP, the polymer (1) can be used in the range of use in the production method of the present invention, and is usually added in an amount of 0.0001 to 10 mass% relative to 100 mass% of the aqueous medium.
In the polymerization of the FEP, cyclohexane, methanol, ethanol, propanol, ethane, propane, butane, pentane, hexane, carbon tetrachloride, chloroform, methylene chloride, methyl chloride, etc. are preferably used as the chain transfer agent, and ammonium carbonate, disodium hydrogen phosphate, etc. are preferably used as the pH buffer.
The aqueous dispersion of FEP obtained by the production method of the present invention may be subjected to post-treatment such as concentration, dried, powdered, and melt-extruded as needed, thereby producing pellets. The aqueous medium in the aqueous dispersion of FEP may contain an additive such as a nonionic surfactant, or may contain a water-soluble organic solvent such as a water-soluble alcohol, or may not contain a water-soluble organic solvent, if necessary.
In addition, the melt extrusion may be performed by appropriately setting extrusion conditions as long as the extrusion conditions are extrusion conditions under which pelletization is usually possible.
In the production method of the present invention, the FEP obtained may have-CF at the site of at least one of the polymer main chain and the polymer side chain 3 、-CF 2 H and other terminal groups, preferably-COOH, -CH 2 OH、-COF、-CF＝CF-、-CONH 2 、-COOCH 3 The content of isothermally labile groups (hereinafter referred to as "labile end groups") is low or absent.
The unstable terminal group is chemically unstable, and therefore, not only lowers the heat resistance of the resin, but also causes an increase in the attenuation amount of the obtained electric wire.
In the production method of the present invention, it is preferable that the polymerization is terminated at a rate of 1X 10 per polymer 6 Unstable terminal group in number of carbon atoms and-CF 2 The H terminal groups were produced so that the total number of H terminal groups was 50 or less. At every 1×10 6 Of the carbon atoms, more preferably less than 20, and still more preferably 5 or less. The above-mentioned unstable terminal group and-CF 2 H terminal groups may also be absent, all-CF 3 End groups.
Unstable terminal group and-CF 2 The H terminal group can be converted to-CF by a fluorination treatment 3 The terminal group stabilizes it. The fluorination treatment method is not particularly limited, and examples thereof include a method in which the polymer is exposed to a fluorine radical source that generates a fluorine radical under the fluorination treatment conditions. As the fluorine radical source, there may be mentioned fluorine gas and CoF 3 、AgF 2 、UF 6 、OF 2 、N 2 F 2 、CF 3 OF and halogen fluoride (e.g. IF 5 、ClF 3 ) Etc. Among them, a method of directly contacting fluorine gas with FEP obtained by the production method of the present invention is preferable, and the contact is preferably performed using diluted fluorine gas having a fluorine gas concentration of 10 to 50 mass% from the viewpoint of reaction control. The diluted fluorine gas can be obtained by diluting fluorine gas with an inert gas such as nitrogen gas or argon gas. The fluorine gas treatment is carried out, for example, at a temperature of 100 to 250 ℃. The processing temperature is not limited to the above range, and may be appropriately set according to the situation. The fluorine gas treatment is preferably performed by continuously or intermittently supplying dilute fluorine gas into the reactor. The fluorination treatment may be performed on a dry powder after polymerization or may be performed on pellets after melt extrusion.
The FEP produced by the production method of the present invention has good moldability, is less likely to cause molding failure, and has good heat resistance, chemical resistance, solvent resistance, insulation, electrical characteristics, and the like.
The method for producing the powder of FEP is a method in which the FEP obtained by the production method of the present invention is dried and powdered to obtain a powder.
The powder may be fluorinated. The method for producing a fluorinated powder is a method in which a fluorinated powder is obtained by supplying fluorine gas to a powder obtained by the method for producing a powder and then fluorinating the powder.
The method for producing pellets of FEP is a method for producing pellets by granulating FEP obtained by the production method of the present invention.
The above pellets may be fluorinated. The above-mentioned method for producing fluorinated pellets is a method in which fluorine gas is supplied to pellets obtained by the above-mentioned method for producing pellets, and the pellets are fluorinated to obtain fluorinated pellets.
Accordingly, the FEP can be used for manufacturing various molded articles such as coating materials for wires, foamed wires, cables, wires, etc., pipes, films, sheets, filaments, etc.
(2) In the production process of the present invention, the polymerization of TFE/perfluoro (alkyl vinyl ether) copolymer such as PFA or MFA and TFE/perfluoro (alkyl allyl ether) copolymer is usually preferably carried out at a polymerization temperature of 10℃to 100℃and a polymerization pressure of 0.3MpaG to 6.0 MpaG.
The preferred monomer composition (mole%) of the TFE/perfluoro (alkyl vinyl ether) copolymer is TFE: perfluoro (alkyl vinyl ether) = (90 to 99.7): (0.3 to 10), more preferably (97 to 99): (1-3). As the above perfluoro (alkyl vinyl ether), the formula: CF (compact flash) 2 ＝CFORf 4 (wherein Rf 4 A perfluoroalkyl group having 1 to 6 carbon atoms).
In addition to TFE and perfluoro (alkyl vinyl ether), other monomers copolymerizable with these monomers are polymerized, whereby a copolymer of TFE, perfluoro (alkyl vinyl ether) and other monomers can be obtained as TFE/perfluoro (alkyl vinyl ether) copolymer. As other monomers, the above-mentioned fluoromonomers (excluding TFE and perfluoro (alkyl vinyl ether)) and non-fluoromonomers are exemplified. As the other monomer, 1 or more kinds may be used. The content of the other monomer units in the TFE/perfluoro (alkyl vinyl ether) copolymer may be 0.1 to 2 mass% with respect to the total monomer units.
The preferred monomer composition (mole%) of the TFE/perfluoro (alkyl allyl ether) copolymer is TFE: perfluoro (alkyl allyl ether) = (90 to 99.7): (0.3 to 10), more preferably (97 to 99): (1-3). As the above perfluoro (alkyl allyl ether), the formula: CF (compact flash) 2 ＝CFCF 2 ORf 4 (wherein Rf 4 A perfluoroalkyl group having 1 to 6 carbon atoms).
In addition to TFE and perfluoro (alkyl allyl ether), other monomers copolymerizable with these monomers are polymerized, whereby a copolymer of TFE, perfluoro (alkyl allyl ether) and other monomers can be obtained as TFE/perfluoro (alkyl allyl ether) copolymer. As other monomers, the above-mentioned fluoromonomers (excluding TFE and perfluoro (alkylallyl ether)) and non-fluoromonomers are exemplified. As the other monomer, 1 or more kinds may be used. The content of the other monomer units in the TFE/perfluoro (alkyl allyl ether) copolymer may be 0.1 to 2 mass% with respect to the total monomer units.
In the polymerization of the TFE/perfluoro (alkyl vinyl ether) copolymer and the TFE/perfluoro (alkyl allyl ether) copolymer, the polymer (1) can be used in the range of use in the production method of the present invention, and is usually added in an amount of 0.0001 to 10 mass% relative to 100 mass% of the aqueous medium.
In the polymerization of the TFE/perfluoro (alkyl vinyl ether) copolymer and TFE/perfluoro (alkyl allyl ether) copolymer, cyclohexane, methanol, ethanol, propanol, propane, butane, pentane, hexane, carbon tetrachloride, chloroform, methylene chloride, methyl chloride, methane, ethane, etc. are preferably used as the chain transfer agent, and ammonium carbonate, disodium hydrogen phosphate, etc. are preferably used as the pH buffer.
The aqueous dispersion of TFE/perfluoro (alkyl vinyl ether) copolymer and TFE/perfluoro (alkyl allyl ether) copolymer obtained by the production method of the present invention is optionally post-treated such as concentrated, dried, powdered, and melt extruded to obtain pellets. The aqueous medium in the aqueous dispersion may contain an additive such as a nonionic surfactant, or may contain a water-soluble organic solvent such as a water-soluble alcohol, or may not contain a water-soluble organic solvent, if necessary.
In addition, the melt extrusion may be performed by appropriately setting extrusion conditions as long as the extrusion conditions are extrusion conditions under which pelletization is usually possible.
Among the above copolymers, the fluorine gas treatment is preferably performed for the purpose of improving the heat resistance and further enhancing the effect of suppressing the permeation of the agent in the molded article.
Fluorine gas treatmentBy contacting fluorine gas with the copolymer. However, since the reaction with fluorine has very high exothermic properties, it is preferable to dilute fluorine with an inert gas such as nitrogen. The amount of fluorine in the fluorine gas/inert gas mixture is 1 to 100% by mass, preferably 10 to 25% by mass. The treatment temperature is 150-250 ℃, preferably 200-250 ℃, and the fluorine gas treatment time is 3-16 hours, preferably 4-12 hours. The gas pressure for fluorine gas treatment is in the range of 1 to 10 gas pressure, and preferably atmospheric pressure is used. In the case of using the reactor at atmospheric pressure, the fluorine/inert gas mixture may be continuously introduced into the reactor. As a result, the unstable terminal of the copolymer was converted into-CF 3 The terminal end is thermally stable.
As a molding method of the copolymer and the composition thereof, a molding method such as compression molding, transfer molding, extrusion molding, injection molding, blow molding, and the like can be applied similarly to the conventional PFA.
The desired molded product can be obtained by such a molding method, and examples of the molded product include a sheet, a film, a gasket, a round bar, a square bar, a tube blank, a tube, a round groove, a square groove, a can, a wafer carrier, a wafer box, a beaker, a filter housing, a flowmeter, a pump, a valve, a cock, a connector, a nut, an electric wire, a heat-resistant electric wire, and the like.
Among these, the present invention can be suitably used particularly in various chemical reaction apparatuses, semiconductor manufacturing apparatuses, pipes, tube blanks, tanks, connectors, and the like for use in acid-based or alkali-based reagent supply apparatuses and the like, which require impermeability to reagents.
Further, a nonionic surfactant may be added to an aqueous dispersion of TFE/perfluoro (alkyl vinyl ether) copolymer and TFE/perfluoro (alkyl allyl ether) copolymer such as PFA and MFA, and if necessary, polyether sulfone, polyamide imide and/or polyimide and metal powder may be dissolved or dispersed in an organic solvent to obtain a primer composition. The method for coating a metal surface with a fluororesin is also applicable, and comprises the following steps: the primer composition is applied to the metal surface, and the melt-processible fluororesin composition is applied to the primer layer thus formed, and firing of the melt-processible fluororesin composition layer is performed together with the primer layer.
(4) The electrolyte polymer precursor may also be produced using the production method of the present invention. In the production method of the present invention, the polymerization of the electrolyte polymer precursor is preferably carried out at a polymerization temperature of 10℃to 100℃and a polymerization pressure of 0.1MPaG to 2.0 MPaG. The electrolyte polymer precursor contains-SO 2 X 151 、-COZ 151 or-POZ 152 Z 153 (X 151 、Z 151 、Z 152 And Z 153 As described below) can be converted into an ion-exchange polymer by hydrolysis.
Examples of the monomer used for the electrolyte polymer precursor include
General formula (150): CF (compact flash) 2 ＝CF-O-(CF 2 CFY 151 -O) n -(CFY 152 ) m -A 151
(wherein Y is 151 Represents fluorine atom, chlorine atom, -SO 2 F group or perfluoroalkyl group. Perfluoroalkyl groups may contain etheric oxygen and-SO 2 And F base. n represents an integer of 0 to 3. n Y' s 151 May be the same or different. Y is Y 152 Represents fluorine atoms, chlorine atoms or-SO 2 And F base. m represents an integer of 1 to 5. m Y' s 152 May be the same or different. A is that 151 Representation of-SO 2 X 151 、-COZ 151 or-POZ 152 Z 153 。X 151 Representation F, cl, br, I, -OR 151 or-NR 152 R 153 。Z 151 、Z 152 And Z 153 Identical or different, representing-NR 154 R 155 OR-OR 156 。R 151 、R 152 、R 153 、R 154 、R 155 And R is 156 Identical or different, represents H, ammonium, an alkali metal, an alkyl group with or without a fluorine atom, an aryl group, or a sulfonyl group). Examples of the monomer used for the electrolyte polymer precursor include 2 fluorosulfonyl group-containing compounds described in International publication No. 2007/013252 having-SO as described in International publication No. 2014/175123 2 And perfluoromonomers of F group and dioxolane. The preferred monomer composition (mole%) of the electrolyte polymer precursor is TFE: vinyl ether= (50 to 99): (50 to 1), more preferably TFE: vinyl ether= (50-93): (50-7).
The electrolyte polymer precursor may be modified with the 3 rd monomer in the range of 0 to 20 mass% of the total monomers. Examples of the 3 rd monomer include CTFE, vinylidene fluoride, perfluoroalkyl vinyl ether, and perfluorobutenyl vinyl ether; cyclic monomers such as perfluoro-2, 2-dimethyl-1, 3-dioxolane and perfluoro-2-methylene-4-methyl-1, 3-dioxole; and a multifunctional monomer such as divinylbenzene.
The electrolyte polymer precursor thus obtained may be subjected to hydrolysis with an alkali solution and treatment with an inorganic acid after being formed into a film shape, for example, and used as a polymer electrolyte membrane for fuel cells, electrolytic devices, redox flow batteries, and the like.
In addition, the electrolyte polymer dispersion may be obtained by performing hydrolysis with an alkali solution while maintaining the dispersion state of the electrolyte polymer precursor.
Then, the mixture is heated to 120℃or higher in a pressurized container, and then dissolved in a water/alcohol mixed solvent, for example, to prepare a solution.
The solution thus obtained can be used as a binder for an electrode, for example, or can be compounded with various additives and cast into a film for use in, for example, an antifouling coating film, an organic actuator, or the like.
The melt-processible fluororesin powder can be suitably used as a powder coating material. When the powder coating material composed of the melt-processible fluororesin powder is applied to a substrate, a coating film having a smooth surface can be obtained. The melt-processible fluororesin powder having an average particle diameter of 1 μm or more and less than 100 μm is particularly suitable as a powder coating material for electrostatic coating, and the melt-processible fluororesin powder having an average particle diameter of 100 μm or more and 1000 μm or less is particularly suitable as a powder coating material for spin coating or spin molding.
The melt-processible fluororesin powder may be produced by a method of drying and powdering the melt-processible fluororesin obtained by the production method of the present invention to obtain a powder. The method for producing the melt-processible fluororesin powder is also one of the present invention.
(III) perfluoroelastomer
In the production method 1 of the present invention, a perfluoroelastomer can be produced as a fluoropolymer by polymerizing a perfluoromonomer such as TFE.
The perfluoromonomer used in the polymerization of the perfluoroelastomer is preferably selected from the group consisting of
Tetrafluoroethylene [ TFE ],
Hexafluoropropylene [ HFP ]
A general formula: CF (compact flash) 2 ＝CF-ORf 13
(wherein Rf 13 A perfluoroalkyl group having 1 to 8 carbon atoms), a fluorine-containing monomer,
A general formula: CF (compact flash) 2 ＝CFOCF 2 ORf 14
(wherein Rf 14 Is a linear or branched perfluoroalkyl group having 1 to 6 carbon atoms, a cyclic perfluoroalkyl group having 5 to 6 carbon atoms, a linear or branched perfluorooxyalkyl group having 2 to 6 carbon atoms containing 1 to 3 oxygen atoms), and a fluorinated monomer represented by the following formula
A general formula: CF (compact flash) 2 ＝CFO(CF 2 CF(Y 15 )O) m (CF 2 ) n F
(wherein Y is 15 Represents a fluorine atom or a trifluoromethyl group. m is an integer of 1 to 4. n is an integer of 1 to 4) and at least 1 kind of the fluorine-containing monomer.
In addition, in the polymerization of the perfluoromonomer, the monomer providing a crosslinking site may be polymerized together with the perfluoromonomer.
The polymerization of the perfluorinated monomers may also be carried out in the presence of a polymerization initiator. As regards the polymerization initiator, it is described above. The amount of the polymerization initiator to be added is preferably 0.0001 to 10% by mass, more preferably 0.01 to 5% by mass, based on 100% by mass of the perfluoromonomer. By setting the addition amount (presence amount) of the polymerization initiator in the above polymerization to be within the above range, the polymerization reaction of the perfluoromonomer proceeds smoothly, and the perfluoroelastomer can be produced efficiently. If the amount of the polymerization initiator added is too small, a sufficient polymerization rate cannot be obtained or a sufficient yield cannot be obtained.
The polymerization of the perfluorinated monomers may also be carried out in the presence of a pH adjuster. By conducting the polymerization in the presence of the pH adjuster, the adhesion of the perfluoroelastomer to the polymerization vessel can be further suppressed, while a sufficient amount of perfluoroelastomer particles can be produced at a sufficient polymerization rate. The pH adjustor can be added before the polymerization is started or after the polymerization is started.
As the pH adjuster, ammonia water, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, ammonium carbonate, sodium bicarbonate, potassium bicarbonate, ammonium bicarbonate, sodium phosphate, potassium phosphate, sodium hydrogen phosphate, sodium dihydrogen phosphate, potassium hydrogen phosphate, potassium dihydrogen phosphate, sodium citrate, potassium citrate, ammonium citrate, sodium gluconate, potassium gluconate, ammonium gluconate, and the like can be used.
The perfluoroelastomer is preferably a perfluoroelastomer containing TFE, and for example, at least 1 selected from the group consisting of a fluoromonomer copolymer represented by TFE/formula (160), (130) or (140) and a fluoromonomer/crosslinking site-providing monomer copolymer represented by TFE/formula (160), (130) or (140).
The composition of the TFE/PMVE copolymer is preferably 45 to 90/10 to 55 (mol%), more preferably 55 to 80/20 to 45, still more preferably 55 to 70/30 to 45, and most preferably 56 to 69.5/30.5 to 44.
In the case of TFE/PMVE/monomer copolymer providing crosslinking sites, it is preferably 45 to 89.9/10 to 54.9/0.01 to 4 (mol%), more preferably 55 to 77.9/20 to 49.9/0.1 to 3.5, still more preferably 55 to 69.8/30 to 44.8/0.2 to 3, most preferably 55.3 to 69.5/30.3 to 44.5/0.2 to 2.8.
In the case of the fluoromonomer copolymer represented by the general formula (160), (130) or (140) having 4 to 12 TFE/carbon atoms, it is preferably 50 to 90/10 to 50 (mol%), more preferably 60 to 88/12 to 40, still more preferably 65 to 85/15 to 35, and most preferably 66 to 84/16 to 34.
In the case of TFE/a fluoromonomer represented by the general formula (160), (130) or (140) having 4 to 12 carbon atoms/a monomer copolymer providing a crosslinking site, it is preferably 50 to 89.9/10 to 49.9/0.01 to 4 (mol%), more preferably 60 to 87.9/12 to 39.9/0.1 to 3.5, still more preferably 65 to 84.8/15 to 34.8/0.2 to 3, and most preferably 66 to 84.3/15.5 to 33.8/0.2 to 2.8.
When the composition is outside this range, the properties as a rubber elastomer are lost, and the properties tend to be close to those of a resin.
The perfluoroelastomer is preferably at least 1 selected from the group consisting of a fluoromonomer/fluoromonomer copolymer providing a crosslinking site represented by TFE/formula (140), a perfluorovinyl ether copolymer represented by TFE/formula (140), a fluoromonomer copolymer represented by TFE/formula (160), and a fluoromonomer/monomer copolymer providing a crosslinking site represented by TFE/formula (160).
As the perfluoroelastomer, there may be mentioned perfluoroelastomers described in Japanese patent application laid-open No. 97/24381, japanese patent application laid-open No. 61-57324, japanese patent application laid-open No. 4-81608, japanese patent application laid-open No. 5-13961, and the like.
The glass transition temperature of the perfluoroelastomer is preferably-70℃or higher, more preferably-60℃or higher, and still more preferably-50℃or higher, because of excellent compression set characteristics at high temperature. In addition, from the viewpoint of good cold resistance, it is preferably 5 ℃ or less, more preferably 0 ℃ or less, and still more preferably-3 ℃ or less.
The glass transition temperature can be determined as follows: using a differential scanning calorimeter (manufactured by Mettler Toredo corporation, DSC822 e), a DSC curve was obtained by heating 10mg of a sample at 10 ℃/min, and the point at which the maximum value was obtained in the differential curve of the DSC curve at the time of the second-order phase transition was obtained as the glass transition temperature.
From the viewpoint of good heat resistance, the Mooney viscosity ML (1+20) of the perfluoroelastomer at 170℃is preferably 30 or more, more preferably 40 or more, and still more preferably 50 or more. In addition, from the viewpoint of good workability, it is preferably 150 or less, more preferably 120 or less, and further preferably 110 or less.
From the viewpoint of good heat resistance, the Mooney viscosity ML (1+20) of the perfluoroelastomer at 140℃is preferably 30 or more, more preferably 40 or more, and still more preferably 50 or more. In addition, from the viewpoint of good workability, it is preferably 180 or less, more preferably 150 or less, and further preferably 110 or less.
From the viewpoint of good heat resistance, the Mooney viscosity ML (1+10) of the perfluoroelastomer at 100℃is preferably 10 or more, more preferably 20 or more, and still more preferably 30 or more. In addition, from the viewpoint of good workability, it is preferably 120 or less, more preferably 100 or less, and further preferably 80 or less.
The Mooney viscosity can be measured at 170℃or 140℃and 100℃according to JIS K6300 using a Mooney viscometer MV2000E type manufactured by ALPHA TECHNOLOGIES.
According to the production method 1 of the present invention, an aqueous dispersion of a perfluoroelastomer can be obtained as a fluoropolymer. The solid content concentration (perfluoroelastomer content) of the obtained perfluoroelastomer aqueous dispersion is preferably 10 to 50% by mass, more preferably 15 to 40% by mass, and still more preferably 20 to 30% by mass at the time of termination of polymerization.
The solid content concentration (perfluoroelastomer content) of the aqueous perfluoroelastomer dispersion can be specified by drying 1g of the aqueous dispersion at 150℃for 60 minutes, measuring the mass of the heated residue, and calculating the ratio of the mass of the heated residue to the mass of the aqueous dispersion.
The aqueous dispersion of the perfluoroelastomer may be subjected to a treatment such as precipitation or heating.
The above precipitation may be carried out by adding a precipitating agent to the aqueous dispersion. Examples of the precipitating agent include acids such as hydrochloric acid, nitric acid, hydrofluoric acid, sulfuric acid, and trifluoroacetic acid, and preferably at least 1 selected from the group consisting of nitric acid and hydrochloric acid.
The precipitated perfluoroelastomer may be washed with water to remove a small amount of impurities such as a buffer solution and a salt present in the perfluoroelastomer, and then the washed perfluoroelastomer may be dried. The drying temperature is preferably 40 to 200 ℃, more preferably 50 to 180 ℃, still more preferably 70 to 150 ℃.
The form of the perfluoroelastomer obtained after precipitation is not particularly limited, and may be a gum (gum), a pellet (column), a powder, a pellet, or the like, and is preferably a gum or a pellet. The gum block (gum) is a granular small block made of perfluoroelastomer, and the lump (column) is a form in which perfluoroelastomer cannot be fused to each other at room temperature in a small granular form as a gum block, thereby forming an amorphous block. The gel mass or agglomerate is obtained by precipitation, drying, or the like, from the aqueous dispersion obtained by the production method of the present invention, by appropriately using a conventionally known method.
In the production method of the present invention, the perfluoroelastomer in the aqueous dispersion may be precipitated with an acid having no metal element, and the perfluoroelastomer after precipitation may be washed with a liquid medium having a reduced content of the metal element. Further, in the production method of the present invention, the washed perfluoroelastomer may be dried. By such a production method, a perfluoroelastomer having a metal content of 10 mass ppm or less can be produced. As the liquid medium, water is preferable, and ultrapure water is further preferable. The metal content of the liquid medium is preferably 2 mass ppm or less, more preferably 1 mass ppm or less, and still more preferably 0.5 mass ppm or less. In addition, in the manufacturing method of the present invention, the manufacturing method described in international publication No. 2018/225586 can be used. According to such a production method, a perfluoroelastomer having a reduced metal content can be produced, and a perfluoroelastomer suitable for components of a semiconductor production apparatus can be produced.
The polymer (1), a decomposed product or by-product of the polymer (1) by-produced from the polymer (1), a residual monomer, or the like is recovered from the waste water produced by the above-mentioned precipitation or washing and/or the waste gas produced by drying, and is purified, whereby the polymer (1), the decomposed product or by-product of the polymer (1) by-produced from the polymer (1), the residual monomer, or the like can be reused. The method for recovering and purifying the above-mentioned aqueous solution is not particularly limited, and may be carried out by a known method. For example, the method described in JP 2011-52020A can be used.
In the production method of the present invention, when the fluoropolymer is precipitated, washed, dried, or the like, waste water and waste gas are generated. The polymer (1), a decomposed product or by-product of the polymer (1) by-produced from the polymer (1), a residual monomer, or the like is recovered from the waste water produced by the precipitation or washing and/or the waste gas produced by drying, and is purified, whereby the polymer (1), the decomposed product or by-product of the polymer (1) by-produced from the polymer (1), the residual monomer, or the like can be reused. The method for recovering and purifying the above-mentioned aqueous solution is not particularly limited, and may be carried out by a known method. Examples of the method described in japanese patent application laid-open No. 2007/15937, us patent application laid-open No. 2007/25902, and us patent application laid-open No. 2007/27251 include the following methods.
The method for recovering the polymer (1) from the wastewater, and the decomposed product, by-product, residual monomer, and the like of the polymer (1) by-produced from the polymer (1) includes the following methods: the wastewater is brought into contact with adsorption particles such as ion exchange resin, activated carbon, silica gel, clay, zeolite, etc., the polymer (1) and the like are adsorbed, and then the wastewater and the adsorption particles are separated. When the adsorption particles having adsorbed the polymer (1) and the like are incinerated, the polymer (1) and the like can be prevented from being released into the environment.
The polymer (1) and the like may be separated and eluted from the ion exchange resin particles to which the polymer (1) and the like are adsorbed by a known method, and may be recovered. For example, in the case where the ion exchange resin particles are anion exchange resin particles, the polymer (1) or the like can be eluted by bringing the inorganic acid into contact with the anion exchange resin. When a water-soluble organic solvent is subsequently added to the resulting solution, it is usually separated into 2 phases, and therefore, the polymer (1) and the like can be recovered by recovering the lower phase containing the polymer (1) and the like and neutralizing. The water-soluble organic solvent includes polar solvents such as alcohols, ketones, and ethers.
Other methods for recovering the polymer (1) and the like from the ion exchange resin particles include a method using an ammonium salt and a water-soluble organic solvent, and a method using an alcohol and an acid as desired. In the latter method, the ester derivative of the polymer (1) or the like is produced, and thus can be easily separated from the alcohol by distillation.
In the case where the wastewater contains fluoropolymer particles or other solid components, it is preferable to remove the wastewater before contacting the wastewater with the adsorbent particles. Examples of the method for removing the fluoropolymer particles and other solid components include a method for separating wastewater and precipitate after precipitating them by adding an aluminum salt or the like, and an electrocoagulation method. Further, the removal may be performed mechanically, and examples thereof include a cross flow filtration method, a depth filtration method, and a precoat filtration method.
From the viewpoint of productivity, the concentration of the non-coagulated fluoropolymer in the wastewater is preferably low, and the concentration is more preferably less than 0.4 mass%, particularly preferably less than 0.3 mass%.
As a method for recovering the polymer (1) or the like from the above exhaust gas, there is a method for obtaining a scrubbing solution containing the polymer (1) or the like by contacting with an organic solvent or the like such as deionized water, an aqueous alkali solution, a glycol ether solvent or the like using a scrubber. When a high-concentration aqueous alkali is used as the aqueous alkali, the scrubbing solution can be recovered in a state where the polymer (1) and the like are phase-separated, and thus the recovery and reuse of the polymer (1) and the like are easy. Examples of the alkali compound include alkali metal hydroxides and quaternary ammonium salts.
The scrubbing solution containing the polymer (1) and the like may be concentrated using a reverse osmosis membrane and the like. The concentrated scrubbing solution usually contains fluoride ions, but the polymer (1) and the like can be easily reused by further adding alumina after concentration to remove the fluoride ions. The polymer (1) and the like may be recovered by the above method by bringing the adsorption particles into contact with the scrubbing solution to adsorb the polymer (1) and the like.
The polymer (1) and the like recovered by any of the above methods can be reused for the production of a fluoropolymer.
The production method of the present invention is a method for producing PTFE by polymerizing TFE in an aqueous medium (hereinafter, sometimes referred to as the production method 2 of the present invention), wherein PTFE is high-molecular-weight PTFE, polymer (1) is a polymer of monomer (1) represented by general formula (1), and the content of dimers and trimers of monomer (1) in polymer (1) is 1.0 mass% or less relative to polymer (1).
Since TFE is polymerized in the presence of the polymer (1), the production method 2 of the present invention can produce PTFE substantially free of dimers and trimers of monomers constituting the polymer (1). In addition, according to the production method of the present invention, PTFE having a high molecular weight can be obtained.
In the production method 2 of the present invention, as the polymer (1), a polymer (1) having a content of polymerized units (1) of 50 mass% or more may be used as in the production method 1 of the present invention, or a polymer (1) having a content of polymerized units (1) of less than 50 mass% may be used.
In the polymer (1) used in the production method 2 of the present invention, the content of the polymerized units (1) is preferably 1.0 mass% or more, 3.0 mass% or more, 5.0 mass% or more, 10 mass% or more, 20 mass% or more, 30 mass% or more, 40 mass% or more, 50 mass% or more, 60 mass% or more, 70 mass% or more, 80 mass% or more, or 90 mass% or more, with respect to all polymerized units. The content of the polymerization unit (1) is particularly preferably substantially 100 mass%, and the polymer (1) is most preferably composed of only the polymerization unit (1).
In the polymer (1) used in the production method 2 of the present invention, the content of polymerized units based on other monomers copolymerizable with the monomer (1) is preferably 99.0 mass% or less, 97.0 mass% or less, 95.0 mass% or less, 90 mass% or less, 80 mass% or less, 70 mass% or less, 60 mass% or less, 50 mass% or less, 40 mass% or less, 30 mass% or less, 20 mass% or less, or 10 mass% or less, with respect to all polymerized units. The content of the polymerized unit based on the other monomer copolymerizable with the monomer (1) is particularly preferably substantially 0 mass%, and the polymer (1) most preferably does not contain the polymerized unit based on the other monomer.
The constitution of the polymer (1) used in the production method 2 of the present invention is the same as that of the polymer (1) used in the production method 1 of the present invention except that the content of the polymerized units (1) can be selected from a wide range.
The 2 nd production method of the present invention preferably includes the steps of: a step of polymerizing the monomer (1) to obtain a crude composition containing a polymer of the monomer (1); and a step of removing the dimer and trimer of the monomer (1) contained in the crude composition from the crude composition to obtain a polymer (1) having a content of the dimer and trimer of the monomer (1) of 1.0 mass% or less with respect to the polymer (1).
In the production method 2 of the present invention, when the polymerization of the monomer (1) and the other monomer copolymerizable with the monomer (1) is performed to obtain the crude composition, the obtained crude composition generally contains a dimer and a trimer composed of the polymerized unit (1) based on the monomer (1) and the polymerized unit based on the other monomer copolymerizable with the monomer (1). By removing the dimer and trimer composed of the polymerized unit (1) and polymerized units based on other monomers contained in the crude composition from the above crude composition, it is possible to obtain a polymer (1) in which the content of the dimer and trimer composed of the polymerized unit (1) and polymerized units based on other monomers is 1.0 mass% or less with respect to the polymer (1).
The polymerization of the monomer (1) can be carried out by the method described in the production method 1 of the present invention.
In the production method 2 of the present invention, the polymerization of the monomer (1) is preferably carried out in an aqueous medium in the substantial absence of a fluorosurfactant (excluding the monomer (1)).
The fluorosurfactant is as described above.
After the polymerization of the monomer (1), dimers and trimers of the monomer (1) contained in the crude composition obtained by the polymerization of the monomer (1) are removed from the crude composition. Means for removing dimers and trimers are described above.
By appropriately selecting the means for removing the dimer and trimer, a component having a molecular weight of 3000 or less, a component having a molecular weight of 2000 or less, a component having a molecular weight of 1500 or less, and a component having a molecular weight of 1000 or less can be removed.
The polymerization of TFE can be carried out by the methods described above. As described above, the modifying monomer may be polymerized with TFE.
The present invention also relates to a composition (hereinafter, sometimes referred to as the 1 st composition of the present invention) comprising a polymer (1) and a fluorine-containing polymer, wherein the fluorine-containing polymer comprises polymerized units based on a perfluorinated monomer, the content of polymerized units based on a perfluorinated monomer in the fluorine-containing polymer is 90 mol% or more relative to the total polymerized units of the fluorine-containing polymer, the polymer (1) is a polymer of a monomer (1) represented by the general formula (1), the polymerized units (1) based on the monomer (1) in the polymer (1) are 50 mass% or more relative to the total polymerized units of the polymer (1), and the content of dimers and trimers of the monomer (1) in the polymer (1) is 1.0 mass% or less relative to the polymer (1).
The 1 st composition of the present invention can be produced by the 1 st production method of the present invention.
The form of the composition 1 of the present invention is not particularly limited, and may be, for example, an aqueous dispersion, a precipitate, a dried product, a gum (gum), a pellet (column), a powder, a granule, or the like. The aqueous dispersion means a dispersion system in which an aqueous medium is used as a dispersion medium and a fluoropolymer is used as a dispersoid. The aqueous medium is not particularly limited as long as it is a liquid containing water, and may contain, for example, an organic solvent such as alcohol, ether, ketone, or paraffin in addition to water.
The composition 1 of the present invention may be an aqueous fluoropolymer dispersion in which primary particles of the fluoropolymer are dispersed in an aqueous medium. The aqueous dispersion may be any of an aqueous dispersion obtained by performing the polymerization, a dispersion obtained by concentrating or performing dispersion stabilization treatment on the aqueous dispersion, and an aqueous dispersion obtained by dispersing a powder composed of a fluoropolymer in an aqueous medium in the presence of the surfactant. The composition of the present invention may be a fluoropolymer powder. The fluoropolymer powder is obtained, for example, by precipitating the fluoropolymer in the aqueous fluoropolymer dispersion by a known method.
The content of the polymer (1) in the composition is preferably 0.001% by mass or more, more preferably 0.005% by mass or more, still more preferably 0.01% by mass or more, particularly preferably 0.05% by mass or more, and most preferably 0.10% by mass or more, relative to the fluorine-containing polymer. The content of the polymer (1) in the composition is preferably 10% by mass or less, more preferably 5.0% by mass or less, further preferably 2.0% by mass or less, particularly preferably 1.0% by mass or less, and most preferably 0.50% by mass or less, based on the fluoropolymer.
The content of the polymer (1) was determined by solid NMR measurement.
Further, measurement methods of polymers and the like are described in International publication No. 2014/099453, international publication No. 2010/075497, international publication No. 2010/075496, international publication No. 2011/008381, international publication No. 2009/055521, international publication No. 1987/007528, japanese patent application laid-open No. 61-293476, international publication No. 2010/075494, international publication No. 2010/075359, international publication No. 2006/119224, international publication No. 2013/085864, international publication No. 2012/0808707, international publication No. 2012/082503, international publication No. 2012/082625, international publication No. 2012/082655, international publication No. 2004/067588, international publication No. 2009/068528, japanese patent application laid-open No. 2004-978, japanese patent application laid-open No. 2001-226466, international publication No. 1992/017, international publication No. 2014/069165, and Japanese patent application laid-open No. 11-181009, respectively. As a method for measuring the content of the polymer (1), the method for measuring the polymer described in each of these documents can be used.
In addition, in the case where the fluorine-containing polymer is a perfluoroelastomer, the content of the polymer (1) can be measured by the following method. The determination can be made by the following method: the composition is mixed with a solvent for dissolving the perfluoroelastomer, deionized water is added to the obtained mixed solution to extract the polymer (1) from the obtained mixed solution, an upper phase (aqueous phase) containing the polymer (1) is recovered, the recovered upper phase is dried by heating, the mass of the residual component (polymer (1)) thus obtained is measured, and the content of the polymer (1) is calculated to measure the content.
The solvent for dissolving the perfluoroelastomer is preferably a perhalogen solvent in which all hydrogen atoms are replaced with halogen atoms, and particularly preferably a perfluorosolvent in which all hydrogen atoms are replaced with fluorine atoms. Specific examples of the perfluoro-based solvent include perfluoro tertiary amines such as perfluoro tri-n-butylamine and perfluoro triethylamine; perfluoro substituted tetrahydrofuran, perfluoro benzene, fluorinert FC-77 (manufactured by 3M Co., ltd.), demnum solvent (manufactured by Dajin industries Co., ltd., principal component: C) 6 F 14 ) R-318 (manufactured by Dajin industries, main component: c (C) 4 F 8 Cl 2 ) Fluorinert FC-43 (manufactured by 3M company, principal component: (C) 4 F 9 ) 3 N) and the like, and from the viewpoint of handling properties, perfluoro-tri-N-butylamine and Fluorinert FC-77 are preferable.
In addition, as the solvent for dissolving the perfluoroelastomer, various fluorine-based solvents are preferably used in addition to the above-exemplified solvents, and specific examples thereof include perfluoroalkanes, HFCs (hydrofluorocarbons), HFEs (hydrofluoroethers), HCFCs (hydrochlorofluorocarbons), and the like, and specific examples thereof include HFE-7100 (manufactured by 3M company, main component: C 4 F 9 OCH 3 ) HFE-7200 (manufactured by 3M company, main component: c (C) 4 F 9 OC 2 H 5 ) Vertrel XF (manufactured by Chemours Co., ltd., principal component: c (C) 5 H 2 F 10 ) Etc.
In the composition 1 of the present invention, the content of the dimer and trimer of the monomer (1) in the polymer (1) is preferably 1.0 mass% or less with respect to the polymer (1). The content of the dimer and trimer in the composition 1 of the present invention is preferably 0.1% by mass or less, more preferably 0.01% by mass or less, further preferably 0.001% by mass or less, particularly preferably 0.0001% by mass or less, relative to the polymer (1).
In the composition 1 of the present invention, the content of the dimer and trimer in the polymer (1) composed of the polymerized unit (1) based on the monomer (1) and the polymerized unit based on the other monomer copolymerizable with the monomer (1) is preferably 1.0 mass% or less with respect to the polymer (1). The content of the dimer and trimer composed of the polymerized unit (1) and the polymerized unit based on another monomer in the composition 1 of the present invention is preferably 0.1% by mass or less, more preferably 0.01% by mass or less, further preferably 0.001% by mass or less, particularly preferably 0.0001% by mass or less, relative to the polymer (1).
The content of the dimer and trimer in the composition 1 of the present invention can be measured by the same method as the content of the dimer and trimer in the polymer (1).
The polymer (1) in the composition 1 of the present invention may contain a component having a molecular weight of 3000 or less, a component having a molecular weight of 2000 or less, a component having a molecular weight of 1500 or less, or a component having a molecular weight of 1000 or less in the same amount as the polymer (1) used in the production method 1 of the present invention, or may not contain these components.
The polymer (1) in the composition 1 of the present invention can have the same constitution as the polymer (1) used in the production method 1 of the present invention.
The fluoropolymer in the composition 1 of the present invention contains polymerized units based on a perfluoromonomer, and the content of polymerized units based on a perfluoromonomer in the fluoropolymer is 90 mol% or more with respect to the total polymerized units of the fluoropolymer. The fluoropolymer in the composition 1 of the present invention can have the same constitution as the fluoropolymer obtained by the production method 1 of the present invention. The fluoropolymer in the composition 1 of the present invention may be, for example, PTFE or perfluoroelastomer. The PTFE may be a TFE homopolymer containing only TFE units, or may be modified PTFE containing TFE units and modified monomer units.
In the case where the fluoropolymer is PTFE or a perfluoroelastomer, the 1 st composition of the present invention preferably contains little or no metal component. The metal content in the composition is preferably 10 mass ppm or less, more preferably 7 mass ppm or less, further preferably 5 mass ppm or less, particularly preferably 1 mass ppm or less. The composition with reduced metal content may be a precipitate or a dry matter. The precipitate is obtained by precipitating the fluoropolymer in the aqueous dispersion, and the dried precipitate is obtained by drying the precipitate.
The metal content in the composition can be determined as follows: the composition was put into a platinum crucible, washed with dilute nitric acid and ultrapure water, ashed with a burner and an electric furnace, thermally decomposed with sulfuric acid and hydrofluoric acid, dissolved in dilute nitric acid, and a measurement solution was prepared, and the contents of 30 metal elements (Fe, na, K, li, be, mg, al, ca, ti, V, cr, mn, co, ni, cu, zn, ga, rb, sr, zr, mo, ag, cd, in, sn, cs, ba, pb, bi, th) were measured using an ICP mass spectrometer (manufactured by Agilent Technologies corporation, agilent 8800) for the obtained measurement solution, and the respective measured values were summed up to obtain the metal content.
In the case where the fluoropolymer is a perfluoroelastomer, the composition 1 of the present invention may further contain a curing agent (crosslinking agent), a filler, and the like. Examples of the curing agent include a polyol, a polyamine, an organic peroxide, an organotin, bis (aminophenol) tetramine, and bis (thioaminophenol).
The perfluoroelastomer composition of the present invention preferably contains at least 1 selected from the group consisting of inorganic nitride, organotin compound, ammonia-generating compound and crosslinking agent.
Examples of the crosslinking agent include crosslinking agents used for peroxide crosslinking, polyol crosslinking, polyamine crosslinking, triazine crosslinking, oxazole crosslinking, imidazole crosslinking, and thiazole crosslinking.
As the crosslinking agent, 2-bis [ 3-amino-4- (N-phenylamino) phenyl ] hexafluoropropane (AFTA-Ph) is preferable from the viewpoints of heat resistance, steam resistance, amine resistance, and good crosslinking property.
The content of the crosslinking agent is preferably 0.05 to 10 parts by mass, more preferably 0.5 to 5 parts by mass, based on 100 parts by mass of the perfluoroelastomer.
Examples of the filler include: organic fillers made of engineering plastics such as polyarylate, polysulfone, polyethersulfone, polyphenylene sulfide, polyoxybenzoate and polytetrafluoroethylene powder; metal oxide fillers such as alumina, silica, yttria, and titania; metal carbide such as silicon carbide, aluminum carbide, etc., metal nitride filler such as silicon nitride, aluminum nitride, etc.; inorganic fillers such as aluminum fluoride, carbon fluoride, barium sulfate, carbon black, silica, clay, and talc.
The content of the filler is preferably 0.5 to 100 parts by mass, more preferably 5 to 50 parts by mass, based on 100 parts by mass of the perfluoroelastomer.
In the field where high purity and non-staining properties are not particularly required, a usual additive, for example, a processing aid, a plasticizer, a colorant, etc., which is blended with the perfluoroelastomer as needed, may be blended, and 1 or 2 or more kinds of usual crosslinking agents or crosslinking aids different from the above may be blended.
The present invention also relates to a composition (hereinafter, sometimes referred to as the 2 nd composition of the present invention) comprising a polymer (1) and PTFE, wherein PTFE is a high molecular weight PTFE, the polymer (1) is a polymer of a monomer (1) represented by the general formula (1), and the content of dimers and trimers of the monomer (1) in the polymer (1) is 1.0 mass% or less relative to the polymer (1).
The 2 nd composition of the present invention can be produced by the 2 nd production method of the present invention.
The composition 2 of the present invention may be an aqueous PTFE dispersion in which PTFE primary particles are dispersed in an aqueous medium. The aqueous dispersion may be any of an aqueous dispersion obtained by performing the polymerization, a dispersion obtained by concentrating or performing dispersion stabilization treatment on the aqueous dispersion, and an aqueous dispersion obtained by dispersing a powder composed of PTFE in an aqueous medium in the presence of the surfactant. The composition of the present invention may be a PTFE powder. The PTFE powder is obtained, for example, by precipitating PTFE in an aqueous PTFE dispersion by a known method.
The content of the polymer (1) in the composition is preferably 0.001 mass% or more, more preferably 0.005 mass% or more, still more preferably 0.01 mass% or more, particularly preferably 0.05 mass% or more, and most preferably 0.10 mass% or more, based on PTFE. The content of the polymer (1) in the composition is preferably 10% by mass or less, more preferably 5.0% by mass or less, further preferably 2.0% by mass or less, particularly preferably 1.0% by mass or less, and most preferably 0.50% by mass or less, relative to PTFE.
The content of the polymer (1) was determined by solid NMR measurement.
Further, measurement methods of polymers and the like are described in International publication No. 2014/099453, international publication No. 2010/075497, international publication No. 2010/075496, international publication No. 2011/008381, international publication No. 2009/055521, international publication No. 1987/007528, japanese patent application laid-open No. 61-293476, international publication No. 2010/075494, international publication No. 2010/075359, international publication No. 2006/119224, international publication No. 2013/085864, international publication No. 2012/0808707, international publication No. 2012/082503, international publication No. 2012/082625, international publication No. 2012/082655, international publication No. 2004/067588, international publication No. 2009/068528, japanese patent application laid-open No. 2004-978, japanese patent application laid-open No. 2001-226466, international publication No. 1992/017, international publication No. 2014/069165, and Japanese patent application laid-open No. 11-181009, respectively. As a method for measuring the content of the polymer (1), the method for measuring the polymer described in each of these documents can be used.
In the composition 2 of the present invention, the content of the dimer and trimer of the monomer (1) in the polymer (1) is preferably 1.0 mass% or less with respect to the polymer (1). The content of the dimer and trimer in the composition 2 of the present invention is preferably 0.1% by mass or less, more preferably 0.01% by mass or less, further preferably 0.001% by mass or less, particularly preferably 0.0001% by mass or less, relative to the polymer (1).
In the composition 2 of the present invention, the content of the dimer and trimer in the polymer (1) composed of the polymerized unit (1) based on the monomer (1) and the polymerized unit based on the other monomer copolymerizable with the monomer (1) is preferably 1.0 mass% or less with respect to the polymer (1). The content of the dimer and trimer composed of the polymerized unit (1) and the polymerized unit based on another monomer in the composition 2 of the present invention is preferably 0.1% by mass or less, more preferably 0.01% by mass or less, further preferably 0.001% by mass or less, particularly preferably 0.0001% by mass or less, relative to the polymer (1).
The content of the dimer and trimer in the 2 nd composition of the present invention can be measured by the same method as the content of the dimer and trimer in the polymer (1).
The polymer (1) in the composition 2 of the present invention may contain a component having a molecular weight of 3000 or less, a component having a molecular weight of 2000 or less, a component having a molecular weight of 1500 or less, or a component having a molecular weight of 1000 or less in the same amount as the polymer (1) used in the production method 2 of the present invention.
The polymer (1) in the composition 2 of the present invention can have the same constitution as the polymer (1) used in the production method 2 of the present invention.
The PTFE in the composition 2 of the present invention can have the same constitution as the PTFE (high molecular weight PTFE) obtained by the production method 2 of the present invention. The PTFE may be a TFE homopolymer containing only TFE units, or may be modified PTFE containing TFE units and modified monomer units.
In the 1 st composition of the present invention and the 2 nd composition of the present invention, the content of the modified PTFE based on the polymerized unit of the modified monomer (hereinafter also referred to as "modified monomer unit") is preferably in the range of 0.00001 mass% to 1 mass% relative to the total polymerized units of PTFE. The lower limit of the content of the modified monomer unit is more preferably 0.0001 mass%, still more preferably 0.001 mass%, and still more preferably 0.005 mass%. The upper limit of the content of the modified monomer unit is preferably 0.80 mass%, 0.70 mass%, 0.50 mass%, 0.30 mass%, 0.20 mass%, 0.15 mass%, 0.10 mass%, or 0.05 mass%. In the present invention, the modified monomer unit refers to a part derived from a modified monomer that is a part of the molecular structure of PTFE.
In the present invention, the content of each monomer unit constituting PTFE can be calculated by appropriately combining NMR, FT-IR, elemental analysis, and fluorescent X-ray analysis according to the kind of monomer. The content of each monomer unit constituting PTFE can also be obtained by calculating the amount of the modifying monomer to be added for polymerization.
When the modified monomer (a) is contained, the content of the polymerized unit based on the modified monomer (a) is preferably in the range of 0.00001 to 1.0 mass% relative to the total polymerized units of PTFE. The lower limit is more preferably 0.0001 mass%, still more preferably 0.0005 mass%, still more preferably 0.001 mass%, still more preferably 0.005 mass%. In order of preference, 0.90 mass%, 0.50 mass%, 0.40 mass%, 0.30 mass%, 0.20 mass%, 0.15 mass%, 0.10 mass%, 0.08 mass%, 0.05 mass%, 0.01 mass%.
The average primary particle diameter of the primary particles of PTFE is preferably 500nm or less, more preferably 400nm or less, and still more preferably 350nm or less. By the production method of the present invention, primary particles having a relatively small average primary particle diameter can be obtained. The smaller average primary particle diameter of the primary particles can be obtained, for example, by adding a modifying monomer to the polymerization system at the initial stage of polymerization of TFE. The lower limit of the average primary particle diameter is not particularly limited, and may be, for example, 50nm or 100nm. The molecular weight is preferably 100nm or more, more preferably 150nm or more.
The average primary particle diameter of the primary particles of PTFE can be measured by a dynamic light scattering method. First, an aqueous PTFE dispersion in which the polymer solid content concentration was adjusted to about 1.0 mass% was prepared, and the measurement was performed by using a dynamic light scattering method, with a measurement temperature of 25 ℃, a refractive index of a solvent (water) of 1.3328, a viscosity of the solvent (water) of 0.8878mpa·s, and a cumulative number of times of 70. For example, ELSZ-1000S (manufactured by Otsuka electronics Co., ltd.) can be used for the dynamic light scattering method.
The aspect ratio of the PTFE is preferably less than 2.00. The aspect ratio is the aspect ratio of the primary particles of PTFE. The upper limit of the aspect ratio of the primary particles of PTFE is 1.90 or less, 1.80 or less, 1.70 or less, 1.60 or less, 1.50 or less, 1.45 or less, 1.40 or less, 1.35 or less, 1.30 or less, 1.20 or less, 1.10 or less in the order of preference. By the production method of the present invention, primary particles having a relatively small aspect ratio can be obtained. The smaller aspect ratio of the primary particles can be obtained, for example, by adding a modifying monomer to the polymerization system at the initial stage of polymerization of TFE.
When the aspect ratio of PTFE is measured using an aqueous PTFE dispersion, an aqueous PTFE dispersion in which the polymer solid content concentration is adjusted to about 1.0 mass% is prepared, and the aspect ratio can be determined from the average value of the ratio of the long diameter to the short diameter by performing image processing on 400 or more randomly extracted particles by observation with a Scanning Electron Microscope (SEM). When the aspect ratio of PTFE is measured using a PTFE powder, an aqueous PTFE dispersion is prepared by irradiating the PTFE powder with an electron beam, adding the PTFE powder to an aqueous solution of a fluorosurfactant, and then applying ultrasonic waves to redisperse the PTFE powder in the aqueous solution. The aspect ratio can be determined by the above method using the aqueous dispersion thus prepared.
The Standard Specific Gravity (SSG) of the PTFE is preferably 2.280 or less, more preferably 2.200 or less, further preferably 2.190 or less, and further preferably 2.180 or less. Further, 2.130 or more is preferable. The SSG was measured by the in-water displacement method according to ASTM D792 using a sample molded according to ASTM D4895-89.
The Thermal Instability Index (TII) of the PTFE may be 20 or more. The Thermal Instability Index (TII) of PTFE can be adjusted to the above range by manufacturing PTFE using the polymer (1), for example. The TII is preferably 25 or more, more preferably 30 or more, and further preferably 35 or more. Particularly preferably 40 or more. The TII described above is determined according to ASTM D4895-89.
The PTFE may have a weight loss temperature of 0.1% or less of 400 ℃. The weight loss temperature of 0.1% of PTFE can be adjusted to the above range by, for example, producing PTFE using the polymer (1).
About 10mg of PTFE powder having no history of heating to 300℃or higher was accurately weighed for a weight loss temperature of 0.1%, and stored in a dedicated aluminum pan, and measured by TG/DTA (differential thermogravimetry simultaneous measurement apparatus). Regarding the weight loss temperature of 0.1%, the aluminum plate is heated under an atmospheric atmosphere at a temperature range of 25 to 600 ℃ at 10 ℃/min, and the temperature corresponding to the point at which the mass is reduced by 0.1 mass% can be specified.
The 1.0% weight loss temperature of the PTFE may be 492℃or lower. The 1.0% weight loss temperature of PTFE can be adjusted to the above range by, for example, producing PTFE using the polymer (1).
About 10mg of PTFE powder having no history of heating to 300℃or higher was accurately weighed for a 1.0% weight loss temperature, and stored in a dedicated aluminum pan, and measured by TG/DTA (differential thermogravimetry simultaneous measurement apparatus). Regarding the 1.0% weight loss temperature, the aluminum plate is heated under an atmospheric atmosphere at a temperature range of 25 ℃ to 600 ℃ at 10 ℃/min, and the temperature corresponding to the point at which the mass is reduced by 1.0 mass% can be specified.
The peak temperature of PTFE is preferably 347 ℃ or lower, more preferably 346 ℃ or lower, and further preferably 345 ℃ or lower. The lower limit of the peak temperature of PTFE may be 333 ℃ or higher and 335 ℃ or higher.
About 10mg of PTFE powder having no history of heating to 300℃or higher was precisely weighed for the peak temperature of PTFE, and stored in a dedicated aluminum pan, and measured by TG/DTA (differential thermogravimetry simultaneous measurement apparatus). The peak temperature may be specified by heating PTFE which has not been heated to a temperature of 300℃or higher at 10℃per minute using TG/DTA (differential thermal gravimetric measuring instrument), and the temperature may be specified to a temperature corresponding to the maximum value appearing in the Differential Thermal (DTA) curve obtained by this.
In one embodiment of the composition 1 and the composition 2 of the present invention, a fluorosurfactant is contained. The fluorosurfactant-containing composition has an advantage of being capable of being stably manufactured with high productivity using the fluorosurfactant.
In one embodiment of the 1 st composition of the present invention and the 2 nd composition of the present invention, the fluorosurfactant is substantially absent. The composition substantially free of the fluorosurfactant needs to be produced by polymerizing a perfluoromonomer such as TFE without using the fluorosurfactant, but can be produced by the production method of the present invention using the polymer (1).
In the present invention, "substantially no fluorosurfactant" means that the content of fluorosurfactant in the composition is 10 mass ppm or less, preferably 1 mass ppm or less, more preferably 100 mass ppb or less, still more preferably 10 mass ppb or less, still more preferably 1 mass ppb or less, and particularly preferably the fluorosurfactant is less than the detection limit as measured by liquid chromatography-mass spectrometry (LC/MS).
The amount of the fluorosurfactant can be quantified by a known method. For example, quantification may be performed by LC/MS analysis.
First, methanol was added to the composition to extract, and the obtained extract was subjected to LC/MS analysis. In order to further improve the extraction efficiency, the treatment may be performed by Soxhlet extraction, ultrasonic treatment, or the like.
Molecular weight information was selected from the obtained LC/MS spectrum, and it was confirmed that the molecular weight information matches the structural formula of the fluorosurfactant as a candidate.
Then, an aqueous solution having a content of 5 or more levels was prepared for the identified fluorosurfactant, LC/MS analysis of the aqueous solution of each content was performed, the relationship between the content and the area of the region with respect to the content was plotted, and a calibration curve was drawn.
Then, the area of the LC/MS chromatogram of the fluorosurfactant in the extract can be converted to the fluorosurfactant content by using a calibration curve.
The composition 1 of the present invention and the composition 2 of the present invention may be suitably used for the above-mentioned uses.
While the embodiments have been described above, it will be understood that various changes in form and details may be made therein without departing from the spirit and scope of the claims.
Examples
Embodiments of the present invention will be described below with reference to examples, but the present invention is not limited to the examples.
The values of the examples were measured by the following methods.
< oxygen concentration in reactor >
For the slave N 2 The gas discharged from the exhaust line of the reactor under flow was measured and analyzed by a low-concentration oxygen analyzer (trade name "PS-820-L", manufactured by Kagaku Kogyo Co., ltd.) to determine the oxygen concentration at the time of the reaction.
< method for measuring the content of a component having a weight average molecular weight (Mw), a number average molecular weight (Mn) and a molecular weight of 3000 or less)
Mw and Mn of the polymer (Polymer K, L, etc.) were purified by Gel Permeation Chromatography (GPC) using 1260Infinity II manufactured by Agilent Technologies, and a column manufactured by Tosoh (1 TSKgel G3000 PW) XL And 1 TSG gel GMPW XL ) For the joint use, a mixed solvent of Tris buffer and acetonitrile (Tris buffer: acetonitrile=8: 2 (v/v)) and the molecular weight was calculated using monodisperse Polyoxyethylene (PEO) and polyethylene glycol (PEG) as standards.
< alternation Rate >
By carrying out the polymerization 19 F-NMR determination from CF appearing in the NMR spectrum 2 ＝CFOCF 2 CF 2 SO 3 "OCF" of Na 2 * "total integrated value of each of 2 peaks (peak appearing at-75 ppm to-80 ppmm and peak appearing at-80 ppm to-84 ppm) is calculated according to the following calculation formula.
The alternation ratio (%) is equal to or more than (b×2)/(a+b) ×100
a: total integrated value of peaks in-75 ppm to-80 ppmm region
b: total integrated value of peaks in-80 ppm to-84 ppm region
The calculated alternation rate is based on CF in the polymer 2 ＝CFOCF 2 CF 2 SO 3 Polymerization of polymerized units of Na adjacent to polymerized units based on VdFProportion of units.
Relative to CF-based 2 ＝C * FOCF 2 CF 2 SO 3 Carbon atoms (C) in polymerized units of Na * ) Based on VdF (C * H 2 ＝CF 2 ) Carbon atoms (C) in the polymerized units of (2) * ) The bonding ratio is determined by the following calculation formula.
Ratio (%) = (b×2)/(a+b) ×100
Relative to CF-based 2 ＝C * FOCF 2 CF 2 SO 3 Carbon atoms (C) in polymerized units of Na * ) Based on VdF (C * H 2 ＝CF 2 ) Carbon atoms (C) in the polymerized units of (2) * ) Other than carbon atoms (based on C ** F 2 ＝C ** FOCF 2 CF 2 SO 3 Carbon atoms (C) in polymerized units of Na ** ) And based on VdF (CH) 2 ＝C ** F 2 ) Carbon atoms (C) in the polymerized units of (2) ** ) The ratio of bonding is determined by the following calculation formula.
Ratio (%) = (a-b)/(a+b) ×100
< method for measuring the content of dimer and trimer of monomer (monomer K, L) in Polymer (Polymer K, L, etc.)
(1) Extraction from aqueous solutions
The solid content of the aqueous solution of the polymer was measured, and an amount of the aqueous solution corresponding to 0.2g of the solid content of the polymer was weighed. Then, together with the water contained in the aqueous solution, water and methanol were added so that the volume ratio of water to methanol was 50/50 (vol%) to obtain a mixed solution containing the polymer and water and methanol. Thereafter, the obtained mixed solution was filtered using an ultrafiltration disk (molecular weight cut-off 3000 Da), and a supernatant containing the polymer was recovered as an extract.
Analysis of the extract was performed using a liquid chromatograph mass spectrometer (Waters, LC-MS acquisition UPLC/TQD) to obtain a chromatogram of the extract.
Regarding the content of dimers and trimers of the monomers contained in the extract liquid, the integral value of peaks from dimers and trimers of the monomers appearing in the chromatogram of the extract liquid is converted into the content of dimers and trimers of the monomers using a calibration curve of the monomers as an analog, thereby obtaining.
(2) Calibration curve of monomer
5 levels of 1ng/mL to 100ng/mL of a known monomer in methanol standard solution were prepared and measured using a liquid chromatograph mass spectrometer (Waters, LC-MS ACQUITY UPLC/TQD). The relationship between the content of each monomer and the integral value of the peak corresponding to the content was plotted to prepare a calibration curve (first approximation) for each monomer. Next, using the calibration curve (first approximation) of each monomer, calibration curves of dimers and trimers of each monomer were prepared.
Measurement apparatus constitution and LC-MS measurement conditions
TABLE 1
TABLE 1
The quantitative limit in the constitution of the measuring apparatus was 1ng/mL.
< content of modified monomer Unit >
Regarding the HFP unit content, a film disk was produced by compression molding PTFE powder, and 982cm was measured based on the infrared absorbance obtained by FT-IR measurement of the film disk -1 Absorbance at/935 cm -1 The ratio of absorbance was multiplied by 0.3 to obtain the result.
< concentration of Polymer (Polymer K, L, etc.)
About 1g of the aqueous polymer solution was dried in a reduced pressure dryer at 60℃for 60 minutes, and the mass of the heated residue was measured, and a value representing the ratio of the mass of the heated residue to the mass (1 g) of the aqueous polymer solution was used as a percentage.
< concentration of solid content of PTFE-containing aqueous Dispersion >
1g of the aqueous dispersion was dried in a blow dryer at 150℃for 60 minutes, and a value expressed as a percentage of the mass of the heated residue relative to the mass of the aqueous dispersion (1 g) was used.
< average primary particle diameter >
An aqueous PTFE dispersion having a solid content of about 1.0% by mass was prepared, and the dispersion was measured at 25℃and 70 times by using ELSZ-1000S (manufactured by Otsuka electronics Co., ltd.). The refractive index of the solvent (water) was 1.3328, and the viscosity of the solvent (water) was 0.8878 mPas.
< aspect ratio >
An aqueous dispersion in which the solid content concentration was diluted to about 1 mass% was observed by a Scanning Electron Microscope (SEM), and 400 or more particles randomly extracted were subjected to image processing, and the average value of the ratio of the long diameter to the short diameter was obtained.
< Standard Specific Gravity (SSG) >)
The sample molded according to ASTM D4895-89 was used and was measured by the substitution method in water according to ASTM D792.
< peak temperature >
About 10mg of PTFE powder having no history of heating to 300℃or higher was accurately weighed for peak temperature, and stored in a dedicated aluminum pan, and measured by TG/DTA (differential thermogravimetry simultaneous measurement apparatus). Regarding the peak temperature, the aluminum plate was heated at 10 ℃/min under an atmospheric air at a temperature range of 25 ℃ to 600 ℃ to obtain a differential heat (DTA) curve, and the temperature corresponding to the maximum value in the obtained differential heat (DTA) curve was taken as the peak temperature.
< Polymer (Polymer K, L, M) content in PTFE powder >
The content of polymer contained in the PTFE powder is determined by passing through solids 19 The spectrum obtained by F-MAS NMR measurement was obtained.
< extrusion pressure >
The extrusion pressure was determined by the method described in JP-A2002-201217, as follows. To 100g of PTFE powder, 21.7g of a lubricant (trade name: isopar H (registered trademark), manufactured by Exxon corporation) was added, and the mixture was mixed in a glass bottle at room temperature for 3 minutes. Next, before extrusion, the glass bottle was left at room temperature (25 ℃) for at least 1 hour to obtain a lubricating resin. The lubricating resin was passed through holes (diameter 2.5mm, margin length 11mm, lead-in angle 30 °) at room temperature at 100:: paste extrusion was performed at a reduction ratio of 1 to obtain a uniform strand (extrusion molding). The extrusion speed, i.e., the pressing speed was set to 20 inches/minute (51 cm/minute). The extrusion pressure was calculated by measuring the load at which the extrusion load reached an equilibrium state during paste extrusion, divided by the cross-sectional area of the barrel used in paste extrusion.
< tensile test >
The tensile test and the measurement of the breaking strength A were carried out by the following methods according to the method described in JP-A2002-201217.
The bar obtained by extrusion of the above paste was heated at 230 ℃ for 30 minutes, thereby removing the lubricant from the bar. Next, the strips (extrusion molded bodies) were cut to an appropriate length, each end was fixed to the collet with a collet spacing of 1.5 inches (38 mm), and heated to 300 ℃ in an air circulation furnace. Next, the collet was separated at a desired speed (elongation speed) to a separation distance corresponding to a desired elongation (total elongation), and a tensile test (elongation test) was performed. The elongation process is essentially as disclosed in U.S. Pat. No. 4,576,869, except that the extrusion speed (51 cm/min, not 84 cm/min) is different. "elongation" refers to the increase in length caused by stretching, usually expressed as a ratio to the original length. In the elongation method, the elongation rate was 1000%/sec, and the total elongation was 2400%.
< breaking Strength A >
The tensile bar obtained in the tensile test (produced by elongating the bar) was held and fixed in a movable jaw having a gauge length of 5.0cm, and the tensile test was performed at a speed of 300 mm/min at 25℃to measure the strength at break as breaking strength A.
< stress relaxation time >
The method described in JP-A2002-201217 was used as follows.
The two ends of the tensile bar obtained in the tensile test described above were attached to a stationary tool to make a bar sample of 8 inches (20 cm) in length that was tensioned. The oven was maintained at 390 c and a holding tool was inserted into the oven through a slot in the side (covered) of the oven. The time required from the moment of insertion into the oven until the strip sample breaks was measured as the stress relaxation time.
< appearance of stretched body >
The appearance of the stretched bar (produced by stretching the bar) obtained in the above tensile test was visually observed and evaluated according to the following criteria.
And (3) uniformity: the appearance of the tensile bars was uniform.
Non-uniformity: cracks, undulations, bulk density, and the like are observed in the drawn tape, and the drawn tape has an uneven appearance.
Preparation example 1 (preparation of Polymer K)
170g of sodium 1, 2-tetrafluoro-2- ((1, 2-trifluoroethyl) oxy) ethane-1-sulfonate (monomer K), 340g of water, ammonium Persulfate (APS) in an amount corresponding to 2.0 mol% relative to the amount of monomer K, N were charged into the reactor 2 Stirring was carried out at 40℃for 72 hours under flow, whereby an aqueous polymer K solution K-1 comprising polymer K as a homopolymer of monomer K was obtained. The oxygen concentration in the reactor was shifted in the range of 15 to 800 ppm by volume.
Water was added to the obtained aqueous solution K-1 of the polymer K to adjust the concentration of the polymer K to 3.8 mass%, followed by ultrafiltration (molecular weight cut-off 6000Da, manufactured by polysulfone) at 25℃under a water pressure of 0.1MPa, and ultrafiltration was performed. The ultrafiltration was continued while water was injected appropriately until the filtrate was finally eluted with 4 times the amount of water relative to the aqueous solution, to obtain an aqueous polymer K solution K-2. The concentration of the aqueous solution obtained was 1.6 mass%.
The aqueous polymer K solution K-2 was analyzed. The weight average molecular weight (Mw) of the resulting polymer K was 1.0X10 4 Number average molecular weight (Mn) of 0.8X10 4 。
The content of dimers and trimers of the monomer K in the aqueous polymer K solution K-2 is 0.1 mass% or less with respect to the polymer K. The content of the component having a molecular weight of 3000 or less in the aqueous polymer K solution K-2 is 0.5% or less. The present aqueous solution was subjected to DLS analysis, and as a result, the particle size could not be measured.
Example 1
Into a glass reactor having an inner volume of 1L and equipped with a stirrer, 496.17g of deionized water, 30g of paraffin wax and 34.38g of an aqueous polymer K solution K-2 were charged, and aqueous ammonia was added to adjust the pH to 10.6. Then, the contents of the reactor were purged with TFE monomer while being heated to 70 ℃ to remove oxygen from the reactor. After that, the content was stirred. After 0.18g of HFP was added to the reactor, TFE monomer was added until a pressure of 0.73MPaG was reached. 2.75mg of Ammonium Persulfate (APS) initiator dissolved in 20g of deionized water was injected into the reactor to bring the reactor to a pressure of 0.83 MPaG. After the initiator injection, a pressure drop occurred and polymerization was observed to begin. TFE monomer is added to the reactor to maintain pressure and polymerization is continued until about 60g of TFE monomer has reacted. After that, the reactor was vented until the pressure in the reactor reached normal pressure, and the content was taken out of the reactor and cooled. Paraffin wax of the supernatant was removed from the PTFE aqueous dispersion.
The solid content concentration of the obtained PTFE aqueous dispersion was 9.7% by mass, and the average primary particle diameter was 184nm.
The resulting PTFE aqueous dispersion was coagulated under high-speed stirring. The coagulated wet powder was dried at 150℃for 18 hours. The results are shown in Table 2.
Example 2
Polymerization was carried out in the same manner as in example 1 except that the amount of the aqueous polymer K solution K-2 was changed to 68.75g, the amount of deionized water was changed to 462.35g, the amount of HFP was changed to 0.54g, and the polymerization was continued until the reaction of about 140g of TFE monomer was completed. The solid content concentration of the obtained PTFE aqueous dispersion was 20.3% by mass, and the average primary particle diameter was 201nm.
The obtained PTFE aqueous dispersion was diluted with deionized water to a solid content of about 10 mass%, and coagulated under high-speed stirring. The coagulated wet powder was dried at 150℃for 18 hours. The results are shown in Table 2.
Example 3
3107g of deionized water, 104g of paraffin wax, 448g of an aqueous solution K-2 of polymer K, 10.74g of an aqueous solution of 0.1% by mass of isopropyl alcohol and 1.25g of an aqueous solution of 0.1% by mass of Triton were charged into a SUS-made reactor having an internal volume of 6L and equipped with a stirrer. Then, ammonia was added to adjust the pH to 9.0, the contents of the reactor were heated to 70 ℃ while sucking, and simultaneously, the reactor was purged with TFE to remove oxygen, and the contents were stirred. After 7.68g of HFP was added to the reactor, TFE was added until a pressure of 0.73MPaG was reached. 17.9mg of Ammonium Persulfate (APS) initiator dissolved in 20g of deionized water was injected into the reactor to bring the reactor to a pressure of 0.83 MPaG. After the initiator injection, a pressure drop occurred and polymerization was observed to begin. TFE was added to the reactor to maintain the pressure constant at 0.78MPaG. The TFE supply and stirring was stopped at the point when the TFE consumed in the reaction reached about 180 g.
Then, the gas in the reactor was slowly released until the pressure in the reactor reached 0.02MPaG. Thereafter, TFE was supplied until the pressure in the reactor reached 0.78MPaG, and stirring was again started to continue the reaction. At the point when the TFE consumed in the reaction reached about 540g, 14.3mg of hydroquinone dissolved in 20g of deionized water was injected into the reactor and the reaction was continued. The TFE supply was stopped at a point when the TFE consumption during the reaction reached about 1250g, and the stirring was stopped to terminate the reaction. After that, the reactor was vented until the pressure in the reactor reached normal pressure, and the content was taken out of the reactor and cooled. Paraffin wax of the supernatant was removed from the PTFE aqueous dispersion.
The solid content concentration of the obtained PTFE aqueous dispersion was 27.5% by mass, and the average primary particle diameter was 170nm.
The obtained PTFE aqueous dispersion was diluted with deionized water to a solid content of about 10 mass%, coagulated under high-speed stirring, and the coagulated wet powder was dried at 210 ℃ for 18 hours. The physical properties of the obtained PTFE powder were measured. The results are shown in Table 2.
The obtained PTFE aqueous dispersion was diluted with deionized water to a solid content of about 10 mass%, and coagulated under high-speed stirring, and the coagulated wet powder was dried at 240 ℃ for 18 hours. The physical properties of the obtained PTFE powder were measured. The results are shown in Table 3.
Preparation example 2
In a vessel, 300ml of Amberlite (IR 120B (H) -HG) was measured, washed with water until the coloration disappeared, 500ml of 1M-HCl was added, and the mixture was stirred at room temperature for 1 hour. Amberlite is filled in the column with the cock to make the acidity of the water flowing to the waste liquid neutral. The aqueous polymer K-2 obtained in preparation example 1 was put into a column with a cock, and the dropwise addition was started. After the completion of the dropwise addition, water was flowed until the dropwise addition liquid became neutral, to obtain an aqueous polymer L-1 comprising a polymer L of 1, 2-tetrafluoro-2- ((1, 2-trifluoroethyl) oxy) ethane-1-sulfonic acid (monomer L). The concentration of the aqueous solution obtained was 1.5 mass%.
The aqueous polymer L solution L-1 was analyzed. Polymer L has a weight average molecular weight (Mw) of 1.0X10 4 Number average molecular weight (Mn) of 0.8X10 4 。
The content of dimers and trimers of the monomer L in the aqueous polymer L solution L-1 is 0.1 mass% or less with respect to the polymer L. The content of the component having a molecular weight of 3000 or less in the aqueous polymer solution L-1 is 0.5% or less. The present aqueous solution was subjected to DLS analysis, and as a result, the particle size could not be measured.
Example 4
To a SUS-made reactor having an internal volume of 6L and equipped with a stirrer, 3087g of deionized water, 104g of paraffin wax, 477g of an aqueous polymer L solution L-1, and 3.58g of an aqueous 0.1% by mass isopropyl alcohol solution were charged. Then, ammonia was added to adjust the pH to 9.0, the contents of the reactor were heated to 70 ℃ while sucking, and simultaneously, the reactor was purged with TFE to remove oxygen, and the contents were stirred. After 5.8g of HFP was added to the reactor, TFE was added until a pressure of 0.73MPaG was reached. 17.9mg of Ammonium Persulfate (APS) initiator dissolved in 20g of deionized water was injected into the reactor to bring the reactor to a pressure of 0.83 MPaG. After the initiator injection, a pressure drop occurred and polymerization was observed to begin. TFE was added to the reactor to maintain the pressure constant at 0.78MPaG. The TFE supply and stirring was stopped at the point when the TFE consumed in the reaction reached about 180 g.
Then, the gas in the reactor was slowly released until the pressure in the reactor reached 0.02MPaG. Thereafter, TFE was supplied until the pressure in the reactor reached 0.78MPaG, and stirring was again started to continue the reaction. At the point when the TFE consumed in the reaction reached about 540g, 14.3mg of hydroquinone dissolved in 20g of deionized water was injected into the reactor and the reaction was continued. The TFE supply was stopped at a point when the TFE consumption during the reaction reached about 1250g, and the stirring was stopped to terminate the reaction. After that, the reactor was vented until the pressure in the reactor reached normal pressure, and the content was taken out of the reactor and cooled. Paraffin wax of the supernatant was removed from the PTFE aqueous dispersion.
The solid content concentration of the obtained PTFE aqueous dispersion was 25.5% by mass, and the average primary particle diameter was 182nm.
The obtained PTFE aqueous dispersion was diluted with deionized water to a solid content of about 10 mass%, coagulated under high-speed stirring, and the coagulated wet powder was dried at 210 ℃ for 18 hours. The physical properties of the obtained PTFE powder were measured. The results are shown in Table 2.
The obtained PTFE aqueous dispersion was diluted with deionized water to a solid content of about 10 mass%, and coagulated under high-speed stirring, and the coagulated wet powder was dried at 240 ℃ for 18 hours. The physical properties of the obtained PTFE powder were measured. The results are shown in Table 3.
Preparation example 3
Into the reactor were charged 6.8g of monomer K represented by 1, 2-tetrafluoro-2- ((1, 2-trifluoroethyl) oxy) ethane-1-sulfonic acid sodium salt, 34g of water, ammonium Persulfate (APS) in an amount corresponding to 1.5 mol% relative to the amount of monomer K, and N 2 After the substitution and degassing, vdF 3.2g was introduced, and the mixture was stirred at 60℃for 2 hours under a closed condition to obtain an aqueous polymer M-1 containing a polymer M as a copolymer of monomers K and VdF. The internal pressure of the reactor was raised to 0.30MPaG after heating, and the reaction was reduced to 0.19MPaG.
The aqueous polymer M-1 containing the obtained polymer M was brought into contact with a dialysis membrane (molecular weight cut-off: 3500Da, made of cellulose) at room temperature, and filtration was performed to obtain an aqueous fluoropolymer solution. The aqueous polymer M solution M-2 was obtained by conducting dialysis membrane purification. The concentration of the obtained aqueous solution was 2.65 mass%.
The polymer composition was examined by analyzing the aqueous solution M-2 of the polymer M obtained by dialysis by NMR, and as a result, the molar ratio of the polymerized units based on the monomer K to the polymerized units based on VdF contained in the polymer was 1.0/1.0. In addition, CF-based in the polymer M 2 ＝CFOCF 2 CF 2 SO 3 The alternation ratio of polymerized units of Na and polymerized units based on VdF is 76% or more.
The weight average molecular weight (Mw) of the resulting polymer M was 15.3X10 4 Number average molecular weight (Mn) of 7.2X10 4 . The content of dimers and trimers of the monomer K in the aqueous solution obtained by performing dialysis is 0.1 mass% or less with respect to the polymer M. In addition, the content of dimers and trimers of the polymerized units based on the monomer K and the polymerized units based on VdF is 0.1 mass% or less with respect to the polymer M. The content of the component having a molecular weight of 3000 or less in the aqueous solution obtained by dialysis was 0.1 mass% or less.
Example 5
Into a glass reactor having an inner volume of 1L and equipped with a stirrer, 490g of deionized water, 30g of paraffin wax and 41.5g of an aqueous polymer M-2 were charged. Further, ammonia was added to adjust the pH to 9.4. Then, the contents of the reactor were purged with TFE monomer while being heated to 70 ℃ to remove oxygen from the reactor. After that, the content was stirred. After 1.26g of HFP was added to the reactor, TFE monomer was added until a pressure of 0.73MPaG was reached. 2.75mg of Ammonium Persulfate (APS) initiator dissolved in 20g of deionized water was injected into the reactor to bring the reactor to a pressure of 0.83 MPaG. After the initiator injection, a pressure drop occurred and polymerization was observed to begin. TFE monomer was added to the reactor to maintain the pressure constant at 0.78MPaG. The supply of TFE monomer and stirring were stopped at the point when the TFE monomer consumed in the reaction reached about 30 g. Then, the gas in the reactor was slowly released until the pressure in the reactor reached 0.02MPaG. Thereafter, TFE monomer was supplied until the pressure in the reactor reached 0.78MPaG, and stirring was again started to continue the reaction. The supply of TFE monomer was stopped at a point when the TFE monomer consumed in the reaction reached about 150g, and the stirring was stopped to terminate the reaction. After that, the reactor was vented until the pressure in the reactor reached normal pressure, and the content was taken out of the reactor and cooled. Paraffin wax of the supernatant was removed from the PTFE aqueous dispersion. The solid content concentration of the obtained PTFE aqueous dispersion was 21.7% by mass, and the average primary particle diameter was 204nm.
The obtained PTFE aqueous dispersion was diluted with deionized water to a solid content of about 10 mass%, and coagulated under high-speed stirring. The coagulated wet powder was dried at 210℃for 18 hours. The results are shown in Table 2.
TABLE 2
TABLE 2
TABLE 3
TABLE 3 Table 3
Next, a method and a composition for producing a perfluoroelastomer will be described with reference to examples.
The numerical values of these examples were measured by the above-described methods unless otherwise stated. The values measured by the methods other than the above were measured by the following methods.
< concentration of solid content of aqueous Dispersion containing perfluoroelastomer >
1g of the aqueous dispersion containing the perfluoroelastomer was dried in a blow dryer at 150℃for 60 minutes, and a value representing the ratio of the mass of the heated residue to the mass of the aqueous dispersion (1 g) was used.
< Polymer adhesion Rate >
The ratio of the mass of polymer deposit adhering to the polymerizer after the polymerization was terminated to the total amount of the polymer (perfluoroelastomer) after the polymerization was terminated (the adhering rate to the polymerizer) was determined by the following formula.
Polymer attachment rate (mass%) =mass of polymer attachment/mass of polymer obtained (including polymer attachment) ×100
Mass of the resulting polymer = mass of aqueous dispersion x solid content concentration of aqueous dispersion (mass%)/100 + mass of polymer attachment
The polymer attachment includes: after polymerization is finished, extracting the aqueous dispersion liquid from the polymerization kettle, and attaching the aqueous dispersion liquid to the inner wall of the polymerization kettle or polymers in the polymerization kettle such as stirring paddles; and a polymer which is free from the aqueous dispersion by coagulation and which is suspended or precipitated without being dispersed in the aqueous dispersion. The mass of the polymer deposit is the mass obtained by drying and removing the moisture contained in the polymer deposit at 120 ℃.
< composition of perfluoroelastomer >
By passing through 19 F-NMR (solid NMR) and Fourier transform infrared spectrophotometry (FT-IR).
< glass transition temperature of perfluoroelastomer >
As the glass transition temperature, a differential scanning calorimeter (DSC 822e, manufactured by Mettler Toredo Co., ltd.) was used, 10mg of the sample was heated at 10 ℃/min to obtain a DSC curve, and the peak top temperature of the differential curve specified in JIS K6240 was used as the glass transition temperature.
< polymerization Rate >
Calculated by the following formula.
Polymerization rate = { weight of aqueous dispersion×solid content concentration/100 }/{ (amount of pure water used in polymerization+amount of water contained in aqueous solution of polymer (1) used in polymerization) ×polymerization time }
The units of the respective amounts in the formulae are as follows.
Weight of aqueous dispersion: g
Concentration of solid content: mass percent of
Pure water amount used in polymerization: kg (kg)
Amount of water contained in the aqueous solution of the polymer (1) used in the polymerization: kg (kg)
Polymerization time: hours of
Polymerization rate: g/(hr. Times.kg)
< average particle diameter >
The average particle diameter (cumulative average particle diameter) of the perfluoroelastomer particles in the aqueous dispersion was measured by a dynamic light scattering method using ELSZ-1000S (manufactured by the tsuka electronics company) and calculated by the cumulative method.
< number of perfluoroelastomer particles in aqueous Dispersion >
The calculation is performed by the following formula.
[ number 1]
In the formula, the average particle diameter is the cumulative average particle diameter calculated by the above method, the number of polymer particles (perfluoroelastomer particle number) is the number of water per 1cc, and the actual measurement value of the specific gravity of the perfluoroelastomer is used as the specific gravity.
Example 6
63.8G of deionized water and 130.0G of an aqueous polymer L-1 (solid content: 1.5 mass%) were added to a stainless steel autoclave (SUS 316, equipped with a universal stirring blade and 1 piece of baffle plate) having an internal volume of 0.5 liter and having no ignition source, and after the pH was adjusted to 5.9 by adding ammonia water, the system was thoroughly replaced with nitrogen gas, and then deaerated, while stirring at 1000rpm, the temperature was raised to 54℃and a mixed gas of Tetrafluoroethylene (TFE) and perfluoromethyl vinyl ether (PMVE) (TFE/PMVE=24/76 mol%) was introduced so that the internal pressure became 0.83 MPa.G. Next, CF is pressed in by nitrogen 2 ＝CFOCF 2 CF(CF 3 )OCF 2 CF 2 After CN (CNVE) 0.259g and deionized water 0.8g, ammonium Persulfate (APS) 1.03g was dissolved in water 2.5g and pressurized with nitrogen to start the reaction.
Since the pressure in the tank was lowered as the polymerization proceeded, when the pressure reached 0.735 MPa.G, 2G of TFE and 2.2G of PMVE were introduced into the autoclave, and fedThe row is boosted. As the reaction proceeds, TFE and PMVE were similarly introduced at a ratio of 60/40 mol%, and the pressure was repeatedly increased and decreased between 0.735 MPa.G and about 0.89 MPa.G, and 28G of TFE and 30.8G of PMVE were introduced until the polymerization was terminated. During the polymerization, at the time when the total amount of TFE fed reached 6, 10, 14, 18, 24g, CF was purged with nitrogen gas 5 times at 0.259g each time 2 ＝CFOCF 2 CF(CF 3 )OCF 2 CF 2 CN and deionized water 0.8g.
Thereafter, the autoclave was cooled to discharge unreacted monomers, thereby obtaining 259g of an aqueous dispersion having a solid content of 22.0% by mass.
The polymerization time was 10.1 hours. The amount of the polymer adhered to the inside of the collection tank was 0.4g, and the adhesion rate was 0.7 mass% when the water was removed by heating.
To 100g of the aqueous dispersion thus obtained, 75g of deionized water was added, followed by mixing and dilution. This mixed dilution was added dropwise to 750g of 35% aqueous hydrochloric acid. While stirring the aqueous hydrochloric acid solution, dropwise addition was performed.
The perfluoroelastomer was precipitated in an aqueous hydrochloric acid solution, and thus the perfluoroelastomer after the precipitation was filtered off, and was transferred to 100g of deionized water, and washed with stirring for 5 minutes. After 5 minutes, the perfluoroelastomer was again filtered off, transferred to 100g of deionized water, and washed with stirring for 5 minutes. Thereafter, 100g of deionized water was repeatedly used to wash the membrane, and the perfluoroelastomer was filtered off at a point in time when the pH of the washing water after washing became 6 or higher. The filtered perfluoroelastomer was dried under vacuum at 70℃for 48 hours. The perfluoroelastomer obtained was 20.8g.
The obtained perfluoroelastomer was analyzed to obtain the following results.
Composition of perfluoroelastomer: TFE/PMVE/cnve=54.0/45.4/0.62 mol%
Glass transition temperature: -6.2 DEG C
Metal content: 2.2ppm
The polymerization rate was 29.4 g/(hr. Times.kg), the cumulative average particle diameter of the perfluoroelastomer particles in the aqueous dispersion was 69.5nm, and the number of perfluoroelastomer particles in the aqueous dispersion was 7.9X10 14 And/cc.
Example 7
To a stainless steel autoclave (SUS 316, with a universal stirring blade and 1 baffle plate) having an internal volume of 0.5 liter and no ignition source, 65.7g of deionized water and 130.0g of an aqueous polymer L-1 (solid content: 1.5 mass%) were added, and then ammonia was added to adjust the pH to 5.9. Next, after the inside of the system was sufficiently replaced with nitrogen gas, the system was degassed, and the temperature was raised to 50 ℃ with stirring at 1000rpm, and then a mixed gas of Tetrafluoroethylene (TFE) and perfluoromethyl vinyl ether (PMVE) (TFE/pmve=25.6/74.4 mol%) was introduced so that the internal pressure became 0.83mpa·g, and after that, 0.141G of Ammonium Persulfate (APS) was dissolved in 1.5G of deionized water and the mixture was pressurized with nitrogen gas to start the reaction.
At the time when the pressure was lowered to 0.783 MPa.G as the polymerization proceeded, diiodo compound I (CF 2 ) 4 I0.416 g was pressed together with deionized water 1.5 g. Next, when the pressure reached 0.735 MPa.G, 2G of TFE and 1.8G of PMVE were introduced into the autoclave, and the pressure was increased. As the reaction proceeds, TFE and PMVE were similarly introduced at a rate of 64.8/35.2 mol%, and pressure increase and pressure decrease were repeated between 0.735 MPa.G and about 0.89 MPa.G. After the reaction had started, 0.0294g of APS was pressed into 1.5g of deionized water with nitrogen every 12 hours to continue the reaction. TFE 44g and PMVE 39.6g were pressed until polymerization was terminated.
Thereafter, the autoclave was cooled to discharge unreacted monomers, whereby 299g of an aqueous dispersion having a solid content of 23.7% by mass was obtained.
The polymerization time was 33.0 hours. The amount of the polymer adhered to the inside of the collection tank was 0.47g, and the adhesion rate was 0.7 mass% when the water was removed by heating.
To 200g of the aqueous dispersion thus obtained, 150g of deionized water was added, followed by mixing and dilution. The mixed dilution was added dropwise to 1300g of a 10% aqueous hydrochloric acid solution. While stirring the aqueous hydrochloric acid solution, dropwise addition was performed.
The perfluoroelastomer was precipitated in an aqueous hydrochloric acid solution, and thus the perfluoroelastomer after the precipitation was filtered off, and was transferred to 1000g of deionized water, and washed with stirring for 5 minutes. After 5 minutes, the perfluoroelastomer was again filtered off, transferred to 100g of deionized water, and washed with stirring for 5 minutes. Thereafter, 100g of deionized water was repeatedly used to wash the membrane, and the perfluoroelastomer was filtered off at a point in time when the pH of the washing water after washing became 6 or higher. The filtered perfluoroelastomer was dried under vacuum at 70℃for 48 hours. The perfluoroelastomer obtained was 51.2g.
The obtained perfluoroelastomer was analyzed to obtain the following results.
Composition of perfluoroelastomer: TFE/pmve=61.3/38.7 mol%
Iodine content: 0.18 mass%
Glass transition temperature: -6.7 DEG C
The polymerization rate was 9.3 g/(hr. Times.kg), the cumulative average particle diameter of the perfluoroelastomer particles in the aqueous dispersion was 129.7nm, and the number of perfluoroelastomer particles in the aqueous dispersion was 1.3X10 14 And/cc.
Example 8
To a stainless steel autoclave (made of SUS316, with stirring blade and 1 piece of baffle plate) having an internal volume of 6 liters and having no ignition source, 831.8g of deionized water and 1756.1g of an aqueous polymer L-1 (solid content concentration: 1.5 mass%) were added, and then ammonia was added to adjust the pH to 5.9. Next, after the inside of the system was sufficiently replaced with nitrogen gas, the system was degassed, and the temperature was raised to 50 ℃ with stirring at 400rpm, and then a mixed gas of Tetrafluoroethylene (TFE) and perfluoromethyl vinyl ether (PMVE) (TFE/pmve=25.6/74.4 mol%) was introduced so that the internal pressure became 0.83mpa·g, and after that, 4.257G of Ammonium Persulfate (APS) was dissolved in 5.0G of deionized water and the mixture was pressurized with nitrogen gas to start the reaction.
When the pressure reached 0.735 MPa.G as the polymerization proceeded, 14G of TFE and 12G of PMVE were introduced into an autoclave and the pressure was increased, and diiodo compound I (CF) as a chain transfer agent was introduced into the autoclave 2 ) 4 I5.11 g was pressed together with deionized water 5.0 g. As the reaction proceeds, TFE and PMVE were similarly introduced at a rate of 65.9/34.1 mol%, and pressure increase and pressure decrease were repeated between 0.735 MPa.G and about 0.87 MPa.G. After the reaction was started, 0.798g of APS was pushed into the reactor with 3.0g of deionized water every 12 hours, followed by the reaction. TFE616g and PMVE 528g are pressed in until the polymerization is terminated. PolymerizationAt the time when the total feed of TFE reached 308, 364, 434, 490g, 1, 2-tetrafluoro-3-iodo-1- ((1, 2-trifluoroethyl) oxy) propane and deionized water were pressurized with nitrogen in 4 portions of 2.08g each.
Thereafter, the autoclave was cooled to release the unreacted monomer, whereby 3776.4g of an aqueous dispersion having a solid content of 29.8% by mass was obtained.
The polymerization time was 30.0 hours. The amount of the polymer adhered to the inside of the collection tank was 0.1g, and the adhesion rate was 0.01 mass% when water was removed by heating.
To 200g of the aqueous dispersion thus obtained, 150g of deionized water was added, followed by mixing and dilution. The mixed dilution was added dropwise to 1300g of a 10% aqueous hydrochloric acid solution. While stirring the aqueous hydrochloric acid solution, dropwise addition was performed.
The perfluoroelastomer was precipitated in an aqueous hydrochloric acid solution, and thus the perfluoroelastomer after precipitation was filtered off, and was transferred to 200g of deionized water, and washed with stirring for 5 minutes. After 5 minutes, the perfluoroelastomer was again filtered off, transferred to 100g of deionized water, and washed with stirring for 5 minutes. Thereafter, 100g of deionized water was repeatedly used to wash the membrane, and the perfluoroelastomer was filtered off at a point in time when the pH of the washing water after washing became 6 or higher. The filtered perfluoroelastomer was dried under vacuum at 70℃for 48 hours. The perfluoroelastomer obtained was 56.4g.
The obtained perfluoroelastomer was analyzed to obtain the following results.
Composition of perfluoroelastomer: TFE/pmve=64.1/35.9 mol%
Iodine content: 0.43 mass%
Mooney viscosity: ML1+10 (100 ℃) =57.
Glass transition temperature: -3.1 DEG C
The polymerization rate was 14.7 g/(hr. Times.kg), the cumulative average particle diameter of the perfluoroelastomer particles in the aqueous dispersion was 116.2nm, and the number of perfluoroelastomer particles in the aqueous dispersion was 2.5X10 14 And/cc.
Example 9
To a stainless steel autoclave (stirring with universal energy made of SUS 316) having an internal volume of 0.5 liter and having no ignition sourcePaddle and 1 baffle) was added with deionized water 118.8g, 78.0g of an aqueous polymer M solution M-2 (solid content concentration: 2.65 mass%) was replaced with nitrogen gas, and the system was degassed, and the temperature was raised to 54℃with stirring at 1000rpm, and a mixed gas of Tetrafluoroethylene (TFE) and perfluoromethyl vinyl ether (PMVE) (TFE/PMVE=24/76 mol%) was introduced so that the internal pressure became 0.83 MPa.G. Then, CF is carried out 2 ＝CFOCF 2 CF(CF 3 )OCF 2 CF 2 After 0.259g of CN (CNVE) was introduced into 2.5g of deionized water by pressing with nitrogen together with 0.8g of deionized water, 1.03g of Ammonium Persulfate (APS) was dissolved and pressed with nitrogen to start the reaction.
Since the pressure in the tank decreased as the polymerization proceeded, when the pressure reached 0.735 MPa.G, 2G of TFE and 2.2G of PMVE were introduced into the autoclave, and the pressure was increased. As the reaction proceeds, TFE and PMVE were similarly introduced at a ratio of 60/40 mol%, and the pressure was repeatedly increased and decreased between 0.735 MPa.G and about 0.89 MPa.G, and 28G of TFE and 30.8G of PMVE were introduced until the polymerization was terminated. During the polymerization, at the time when the total amount of TFE fed reached 6, 10, 14, 18, 24g, CF was purged with nitrogen gas 5 times at 0.259g each time 2 ＝CFOCF 2 CF(CF 3 )OCF 2 CF 2 CN and deionized water 0.8g.
Thereafter, the autoclave was cooled to release the unreacted monomer, whereby 252g of an aqueous dispersion having a solid content of 20.8% by mass was obtained.
The polymerization time was 5.3 hours. The polymer adhered to the inside of the collection tank was 4.0g and the adhesion rate was 7.7 mass% when water was removed by heating.
To 100g of the aqueous dispersion thus obtained, 75g of deionized water was added, followed by mixing and dilution. The mixed dilution was added dropwise to 700g of a 10% aqueous hydrochloric acid solution. While stirring the aqueous hydrochloric acid solution, dropwise addition was performed.
The perfluoroelastomer was precipitated in an aqueous hydrochloric acid solution, and thus the perfluoroelastomer after the precipitation was filtered off, and was transferred to 100g of deionized water, and washed with stirring for 5 minutes. After 5 minutes, the perfluoroelastomer was again filtered off, transferred to 100g of deionized water, and washed with stirring for 5 minutes. Thereafter, 100g of deionized water was repeatedly used to wash the membrane, and the perfluoroelastomer was filtered off at a point in time when the pH of the washing water after washing became 6 or higher. The filtered perfluoroelastomer was dried under vacuum at 70℃for 48 hours. The perfluoroelastomer obtained was 19.1g.
The obtained perfluoroelastomer was analyzed to obtain the following results.
Composition of perfluoroelastomer: TFE/PMVE/cnve=57.1/42.5/0.38 mol%
Glass transition temperature: -5.4 DEG C
The polymerization rate was 50.3 g/(hr. Times.kg), the cumulative average particle diameter of the perfluoroelastomer particles in the aqueous dispersion was 42.0nm, and the number of perfluoroelastomer particles in the aqueous dispersion was 3.4X10 14 And/cc.

Claims (16)

1. A process for producing a fluoropolymer by polymerizing a perfluoromonomer in an aqueous medium in the presence of a polymer (1), wherein,
the content of polymerized units based on the perfluorinated monomer in the fluoropolymer is 90 mol% or more relative to the total polymerized units of the fluoropolymer,
the polymer (1) is a polymer of a monomer (1) shown in the general formula (1),
the amount of the monomer (1) -based polymerized units (1) in the polymer (1) is 50 mass% or more relative to the total polymerized units of the polymer (1),
the content of the dimer and trimer of the monomer (1) in the polymer (1) is 1.0 mass% or less with respect to the polymer (1),
CF 2 ＝CF-O-R-(Rf-SO 3 M) m (1)
wherein R is a single bond or a linking group; rf is a fluorine-containing alkylene group having 1 to 40 carbon atoms or a fluorine-containing alkylene group having 2 to 100 carbon atoms and having an ether bond or a ketone group; m is H, a metal atom, NR 7 4 An imidazolium with or without substituents, a pyridinium with or without substituents, or a phosphonium with or without substituents; r is R 7 Is H or an organic group; m is an integer of 1 or more.
2. The production method according to claim 1, wherein the monomer (1) is a monomer (2) represented by the general formula (2),
CF 2 ＝CF-O-Rf-SO 3 M (2)
wherein Rf and M are as described above.
3. The production method according to claim 1 or 2, wherein the fluorine-containing polymer is polytetrafluoroethylene.
4. The production method according to claim 1 or 2, wherein the fluorine-containing polymer is a perfluoroelastomer.
5. A process for producing polytetrafluoroethylene by polymerizing tetrafluoroethylene in an aqueous medium in the presence of a polymer (1), wherein,
the polytetrafluoroethylene is high molecular weight polytetrafluoroethylene,
the polymer (1) is a polymer of a monomer (1) shown in the general formula (1),
the content of the dimer and trimer of the monomer (1) in the polymer (1) is 1.0 mass% or less with respect to the polymer (1),
CF 2 ＝CF-O-R-(Rf-SO 3 M) m (1)
wherein R is a single bond or a linking group; rf is a fluorine-containing alkylene group having 1 to 40 carbon atoms or a fluorine-containing alkylene group having 2 to 100 carbon atoms and having an ether bond or a ketone group; m is H, a metal atom, NR 7 4 An imidazolium with or without substituents, a pyridinium with or without substituents, or a phosphonium with or without substituents; r is R 7 Is H or an organic group; m is an integer of 1 or more.
6. The method according to claim 5, wherein the monomer (1) is a monomer (2) represented by the general formula (2),
CF 2 ＝CF-O-Rf-SO 3 M (2)
wherein Rf and M are as described above.
7. A composition comprising a polymer (1) and a fluoropolymer, wherein,
the fluoropolymer contains polymerized units based on a perfluoromonomer, the content of polymerized units based on the perfluoromonomer in the fluoropolymer is 90 mol% or more relative to the total polymerized units of the fluoropolymer,
the polymer (1) is a polymer of a monomer (1) shown in the general formula (1),
the amount of the monomer (1) -based polymerized units (1) in the polymer (1) is 50 mass% or more relative to the total polymerized units of the polymer (1),
the content of the dimer and trimer of the monomer (1) in the polymer (1) is 1.0 mass% or less with respect to the polymer (1),
CF 2 ＝CF-O-R-(Rf-SO 3 M) m (1)
wherein R is a single bond or a linking group; rf is a fluorine-containing alkylene group having 1 to 40 carbon atoms or a fluorine-containing alkylene group having 2 to 100 carbon atoms and having an ether bond or a ketone group; m is H, a metal atom, NR 7 4 An imidazolium with or without substituents, a pyridinium with or without substituents, or a phosphonium with or without substituents; r is R 7 Is H or an organic group; m is an integer of 1 or more.
8. The composition according to claim 7, wherein the monomer (1) is a monomer (2) represented by the general formula (2),
CF 2 ＝CF-O-Rf-SO 3 M (2)
wherein Rf and M are as described above.
9. The composition of claim 7 or 8, wherein the polymer (1) is a monomer (1) and a CFR of the formula 11 ＝CR 11 2 Copolymers of the monomers shown, general formula CFR 11 ＝CR 11 2 Wherein R is 11 Independently H, F or a perfluoroalkyl group having 1 to 4 carbon atoms.
10. The fluorine-containing polymer according to claim 9, wherein the content of the polymerized unit (1) based on the monomer (1) is 50 to 94% by mass based on the total polymerized units constituting the polymer (1), based on the general formula CFR 11 ＝CR 11 2 The content of the polymerized units (M) of the monomer is 6 to 50% by mass relative to the total polymerized units constituting the polymer (1), and the formula CFR 11 ＝CR 11 2 Wherein R is 11 Independently H, F or a perfluoroalkyl group having 1 to 4 carbon atoms.
11. Fluoropolymer according to claim 10 wherein the alternation of polymerized units (1) and polymerized units (M) is 40% or more.
12. The composition of any one of claims 7-11, wherein the fluoropolymer is polytetrafluoroethylene.
13. The composition of any of claims 7-11, wherein the fluoropolymer is a perfluoroelastomer.
14. The composition according to claim 12 or 13, wherein the metal content is 10 mass ppm or less.
15. A composition comprising a polymer (1) and polytetrafluoroethylene, wherein,
the polytetrafluoroethylene is high molecular weight polytetrafluoroethylene,
the polymer (1) is a polymer of a monomer (1) shown in the general formula (1),
the content of the dimer and trimer of the monomer (1) in the polymer (1) is 1.0 mass% or less with respect to the polymer (1),
CF 2 ＝CF-O-R-(Rf-SO 3 M) m (1)
wherein R is a single bond or a linking group; rf is a fluorine-containing alkylene group having 1 to 40 carbon atoms or a compound having 2 to 100 carbon atomsA fluorine-containing alkylene group having an ether bond or a ketone group; m is H, a metal atom, NR 7 4 An imidazolium with or without substituents, a pyridinium with or without substituents, or a phosphonium with or without substituents; r is R 7 Is H or an organic group; m is an integer of 1 or more.
16. The composition according to claim 15, wherein the monomer (1) is a monomer (2) represented by the general formula (2),
CF 2 ＝CF-O-Rf-SO 3 M (2)
wherein Rf and M are as described above.
CN202280035302.5A 2021-05-19 2022-05-17 Method for producing fluorine-containing polymer, method for producing polytetrafluoroethylene, and composition Pending CN117321105A (en)

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JP2021-189034 2021-11-19
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