JP2009197134A - Method for producing crosslinking fluorine-containing elastomer composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing a crosslinking fluorine-containing elastomer composition allowing acceleration of vulcanization rate by improving dispersibility of a crosslinking agent to a fluorine-containing elastomer. <P>SOLUTION: The crosslinking fluorine-containing elastomer composition is produced by mixing an organic solvent (A), a fluorine-containing elastomer (B) and a crosslinking agent (C) together and drying the mixture. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for producing a fluorine-containing elastomer composition for crosslinking, and further to a method for producing a fluorine-containing elastomer molded article using the composition.

  Fluorine-containing elastomers have O-rings, hoses, stem seals, shaft seals, etc. in the fields of automobile industry, semiconductor industry, chemical industry, etc. due to their excellent heat resistance, chemical resistance, solvent resistance, fuel oil resistance, etc. It is widely used after being formed into a shape such as a diaphragm. As the fluorine-containing elastomer, a technique for performing a peroxide crosslinking reaction (for example, see Patent Document 1) and a technique for performing a polyol crosslinking reaction (for example, see Patent Document 2 and Patent Document 3) are generally used.

  However, as the technology advances, the required characteristics become more severe, and the sealing performance in a higher temperature environment exceeding 200 ° C. is also required in the aerospace field, semiconductor manufacturing equipment field, chemical plant field, and automobile industry. In addition, it is difficult to sufficiently satisfy the demands of molded products and sealing materials obtained by peroxide crosslinking and polyol crosslinking that are conventionally used.

  On the other hand, attempts have been made to improve the heat resistance by devising a crosslinking system for the required characteristics under such a high temperature environment. For example, a triazine crosslinking system that uses a fluorine-containing elastomer introduced with a cyano group as a crosslinking point and forms a triazine ring with an organotin compound (see, for example, Patent Document 4), and a fluorine-containing elastomer similarly introduced with a cyano group as a crosslinking point An oxazole bridge system in which an oxazole ring is formed by bisaminophenol, an imidazole bridge system in which an imidazole ring is formed by a bisdiaminophenyl compound (see, for example, Patent Document 5), and a thiazole in which a thiazole ring is formed by bisaminothiophenol A composition comprising a crosslinking system (for example, see Patent Document 6), a fluorine-containing elastomer having a carboxyl group as a crosslinking point at the main chain end and / or branched chain, and an oxazole crosslinking agent, imidazole crosslinking agent or thiazole crosslinking agent. For example, it is known Patent Document 7).

  By the way, generally, a crosslinking agent that does not melt at the vulcanization temperature is used, and is directly added to the elastomer in a powder state. For example, a cross-linking agent, which is a solid substance, is directly kneaded with a fluorine-containing elastomer using a kneader or an open roll, and the cross-linking agent is dispersed in the fluorine-containing elastomer. It is difficult to uniformly knead and disperse the agent, so that the kneading is carried out while adding the crosslinking agent little by little, or the kneading itself takes a long time. Even if such a method is adopted, the cross-linking agent may cause poor dispersion in the composition, or the vulcanization speed may be lowered due to this.

JP-A-53-125491 Japanese Patent Publication No.53-4035 JP-A-6-128334 JP 58-152041 A JP 59-109546 A JP-A-8-104789 International Publication No. 00/29479 Pamphlet

  The present invention relates to a method for producing a fluorine-containing elastomer composition for crosslinking, which can improve the dispersibility of a crosslinking agent in a fluorine-containing elastomer and increase the vulcanization speed, and a fluorine-containing elastomer molded article using the composition. An object is to provide a manufacturing method.

  The present invention relates to a method for producing a crosslinking fluorine-containing elastomer composition comprising a step (I) of mixing an organic solvent (A), a fluorine-containing elastomer (B) and a crosslinking agent (C).

  Moreover, in this invention, the process (II) which dries the obtained mixture may be included.

  In the mixing step (I), it is preferable to further mix the filler (D) from the viewpoint that the mixing time is short.

  In the mixing step (I), the organic solvent (A) and the crosslinking agent (C) are mixed to prepare the preliminary mixture (Ia-1), and then the preliminary mixture (Ia-1) and the fluorine-containing elastomer (B) are mixed. It is preferable to knead from the viewpoint of good dispersibility of the crosslinking agent.

  The fluorine-containing elastomer (B) is preferably a non-perfluoro fluorine-containing elastomer (B1) from the viewpoint of good solubility in a solvent.

  The non-perfluoro fluorine-containing elastomer (B1) contains a vinylidene fluoride unit and / or a tetrafluoroethylene unit and at least one other monomer unit copolymerizable therewith, so that the copolymerizability is good. From this point, it is preferable.

Furthermore, as the non-perfluoro fluorine-containing elastomer (B1),
(1) vinylidene fluoride / hexafluoropropylene copolymer,
The use of (2) vinylidene fluoride / tetrafluoroethylene / hexafluoropropylene copolymer or (3) tetrafluoroethylene / vinylidene fluoride / perfluoroalkyl vinyl ether copolymer results in rubber properties of the resulting molded article. It is preferable from a favorable point.

（式中、Ｒ¹は−ＮＨ₂、−ＮＨＲ²、−ＯＨまたは−ＳＨであり、Ｒ²は、フッ素原子または１価の有機基である）
で示される架橋性反応基を少なくとも２個含む架橋剤、
（Ｃ２）式（２）：

で示される架橋剤、
（Ｃ３）式（３）：

（式中、Ｒｆ¹は炭素数１〜１０のパーフルオロアルキレン基である）
で示される架橋剤、および
（Ｃ４）式（４）：

（式中、ｎは１〜１０の整数である）
で示される架橋剤
よりなる群から選ばれる少なくとも１種の架橋剤であることが、得られる成形品の耐熱性が良好な点から好ましい。 As a crosslinking agent (C),
(C1) Formula (1):

(Wherein R ¹ is —NH ₂ , —NHR ² , —OH or —SH, and R ² is a fluorine atom or a monovalent organic group)
A crosslinking agent comprising at least two crosslinkable reactive groups represented by:
(C2) Formula (2):

A cross-linking agent represented by
(C3) Formula (3):

(Wherein Rf ¹ is a C 1-10 perfluoroalkylene group)
And (C4) Formula (4):

(Where n is an integer from 1 to 10)
It is preferable that it is at least 1 sort (s) of crosslinking agent chosen from the group which consists of a crosslinking agent shown by the point with the favorable heat resistance of the molded article obtained.

  The present invention also relates to a fluorine-containing elastomer composition for crosslinking obtained by the method for producing a fluorine-containing elastomer composition for crosslinking according to the present invention.

  The present invention also includes a molding step (III) in which the cross-linking fluorine-containing elastomer composition is cross-linked to form a cross-linked molded article following the mixing step (I) in the method for producing a cross-linking fluoro-containing elastomer composition of the present invention. The present invention also relates to a method for producing a fluorine-containing elastomer molded product.

  The present invention also relates to a fluorine-containing elastomer molded article obtained by the method for producing a fluorine-containing elastomer molded article of the present invention.

（式中、Ｒ¹は−ＮＨ₂、−ＮＨＲ²、−ＯＨまたは−ＳＨであり、Ｒ²は、フッ素原子または１価の有機基である）
で示される架橋性反応基を少なくとも２個含む架橋剤、
（Ｃ２）式（２）：

で示される架橋剤、
（Ｃ３）式（３）：

（式中、Ｒｆ¹は炭素数１〜１０のパーフルオロアルキレン基である）
で示される架橋剤、および
（Ｃ４）式（４）：

（式中、ｎは１〜１０の整数である）
で示される架橋剤
よりなる群から選ばれる少なくとも１種の架橋剤である組成物にも関する。 Further, the present invention is a composition comprising an organic solvent (A) and a crosslinking agent (C), wherein the crosslinking agent (C)
(C1) Formula (1):

(Wherein R ¹ is —NH ₂ , —NHR ² , —OH or —SH, and R ² is a fluorine atom or a monovalent organic group)
A crosslinking agent comprising at least two crosslinkable reactive groups represented by:
(C2) Formula (2):

A cross-linking agent represented by
(C3) Formula (3):

(Wherein Rf ¹ is a C 1-10 perfluoroalkylene group)
And (C4) Formula (4):

(Where n is an integer from 1 to 10)
The composition which is at least 1 sort (s) of crosslinking agent chosen from the group which consists of a crosslinking agent shown by these is also related.

  This crosslinking agent composition may further contain a fluorine-containing elastomer.

  The organic solvent (A) is at least one selected from the group consisting of ketone solvents, amide solvents, ester solvents, ether solvents, sulfolane solvents, and carbonate solvents, and the solubility of the crosslinking agent. Alternatively, it is preferable from the viewpoint of good uniform dispersibility and not hindering the subsequent crosslinking reaction.

  According to the present invention, the dispersibility of the crosslinking agent (C) in the composition is improved by mixing the organic solvent (A), the fluorine-containing elastomer (B), and the crosslinking agent (C), and the vulcanization speed is increased. It is possible to provide a fluorine-containing elastomer composition for crosslinking and a method for producing a fluorine-containing elastomer molded article that can speed up the process.

  First, the manufacturing method of the fluorine-containing elastomer composition for crosslinking of this invention is demonstrated.

  The method for producing a fluorine-containing elastomer composition for crosslinking according to the present invention includes a mixing step (I) in which an organic solvent (A), a fluorine-containing elastomer (B) and a crosslinking agent (C) are mixed.

(I) Mixing step In the mixing step (I), the organic solvent (A), the fluorine-containing elastomer (B), and the crosslinking agent (C) are mixed.

  As described above, the cross-linking agent (C), which is a solid substance, is directly kneaded with the fluorine-containing elastomer (B) using a kneader or an open roll, and the cross-linking agent (C) is dispersed in the fluorine-containing elastomer (B). However, the fluorine-containing elastomer (B) has high surface slipperiness and it is difficult to uniformly knead and disperse the crosslinking agent (C).

  In the mixing step (I) of the production method of the present invention, the organic solvent (A) is present in the mixing field, thereby helping to disperse the cross-linking agent (C) in the fluorine-containing elastomer (B). Instead, it also shortens the mixing time.

  The method of mixing the organic solvent (A), the fluorine-containing elastomer (B) and the crosslinking agent (C) is not particularly limited as long as these components are present in the mixing field. The mixing method of can be illustrated.

Mixing method (Ia):
A method in which the organic solvent (A) and the crosslinking agent (C) are mixed to prepare the preliminary mixture (Ia) and then the preliminary mixture (Ia) and the fluorine-containing elastomer (B) are kneaded.

Mixing method (Ib):
A method in which the organic solvent (A), the fluorine-containing elastomer (B), and the crosslinking agent (C) are mixed to prepare the preliminary mixture (Ib), and then the preliminary mixture (Ib) is kneaded.

Mixing method (Ic):
After preparing the premix (Ic) by mixing the organic solvent (A), a part of the fluoroelastomer (B) and the crosslinking agent (C), the remainder of the premix (Ic) and the fluoroelastomer (B) Kneading method. In this case, the fluorine-containing elastomer (B) added when preparing the preliminary mixture (Ic) is preferably 1 to 50% by mass of the total amount of the fluorine-containing elastomer (B) from the viewpoint of good dispersibility of the crosslinking agent. .

  In the present invention, in addition to the components (A) to (C), additives (described later) such as a filler (D) and a crosslinking accelerator (E) may be blended. Examples of the mixing method for mixing these include the following methods.

Mixing method (Ia-1): After preparing the premix (Ia-1) by mixing the organic solvent (A) and the crosslinking agent (C), the premix (Ia-1), the fluorine-containing elastomer (B) and A method of kneading the filler (D) and the crosslinking accelerator (E) if necessary.

Mixing method (Ia-2): After preparing the preliminary mixture (Ia-2) by mixing the organic solvent (A), the crosslinking agent (C) and, if necessary, the filler (D) and the crosslinking accelerator (E). The method of kneading the premix (Ia-2) and the fluorine-containing elastomer (B).

Mixing method (Ib-1): An organic solvent (A), a fluorine-containing elastomer (B) and a crosslinking agent (C) are mixed to prepare a premix (Ib-1), and then the premix (Ib-1) and , And if necessary, a method of kneading the filler (D) and the crosslinking accelerator (E).

Mixing method (Ib-2): An organic solvent (A), a fluorine-containing elastomer (B), a crosslinking agent (C) and, if necessary, a filler (D) and a crosslinking accelerator (E) are mixed to prepare a premix (Ib -2), after preparing the premix (Ib-2).

Mixing method (Ic-1): An organic solvent (A), a part of the fluorine-containing elastomer (B) and a crosslinking agent (C) are mixed to prepare a premix (Ic-1), and then the premix (Ic- 1) A method of kneading the remainder of the fluorine-containing elastomer (B) and, if necessary, a filler (D) and a crosslinking accelerator (E).

  The filler (D) may be mixed when preparing the premix, or may be mixed when the premix and the fluorine-containing elastomer (B) are kneaded. preferable.

  In the mixing methods (Ia) to (Ic), and further (Ia-1) to (Ic-1), the method for preparing the preliminary mixture is not particularly limited. For example, the fluorine-containing elastomer (B), the crosslinking agent ( C) If necessary, a method of mixing the filler (D), the crosslinking accelerator (E) and the like dissolved or dispersed in the organic solvent (A) can be employed.

  When dissolving the fluorine-containing elastomer (B), the crosslinking agent (C), if necessary, the filler (D), the crosslinking accelerator (E), etc. in the organic solvent (A), the method is not particularly limited. And a method of dissolving by stirring, ultrasonic wave or heating.

  Further, when the fluorine-containing elastomer (B), the crosslinking agent (C), and if necessary, the filler (D), the crosslinking accelerator (E), etc. are dispersed in the organic solvent (A), the method is particularly There is no limitation, and examples include a method using a ball mill, a sand mill, an atlite, a visco mill, a roll mill, a Banbury mixer, a stone mill, a vibrator mill, a dispersin mill, a disk impeller, a jet mill, a dyno mill, and the like. Among these, a jet mill, a roll mill, and a dyno mill are preferable from the viewpoint that impurities hardly enter and continuous production is possible.

  In any of the mixing methods (Ia) to (Ic) and (Ia-1) to (Ic-1), a crosslinking agent composition in which the crosslinking agent (C) is dissolved or dispersed in the organic solvent (A) in advance. It is preferable from the viewpoint of good dispersibility of the crosslinking agent that it is prepared and mixed with other components in the form of the crosslinking agent composition, and further kneaded.

  The extra organic solvent (A) may be obtained by dissolving the fluorine-containing elastomer (B), the crosslinking agent (C), if necessary, the filler (D), the crosslinking accelerator (E) or the like in the organic solvent (A). After the dispersion, it is preferable to remove before the drying step (II) from the viewpoint of saving energy required for drying.

  In addition, in the mixing methods (Ia) to (Ic), and further (Ia-1) to (Ic-1), the method of kneading after preparing the preliminary mixture is not particularly limited, and rolls, kneaders and the like can be used. The method to use etc. is mention | raise | lifted.

  In the present invention, the organic solvent (A) used in the mixing step (I) is removed by completion of the cross-linking molding. The removal of the organic solvent (A) may be performed as a stand-alone process, or may be performed as a second half part or extension of the mixing process, or may be performed during the first half part or during the cross-linking molding process.

  When the drying step (II) is provided as an independent step, the mixture obtained in the mixing step (I) is dried to remove volatile components such as the organic solvent (A).

  The drying temperature is preferably 40 to 130 ° C. from the viewpoint that the organic solvent can be removed and the crosslinking reaction is difficult to proceed. Further, the drying time is preferably 6 to 48 hours from the viewpoint of proceeding with removal of the solvent as much as possible. The drying step (II) may be performed only once or a plurality of times.

  In the fluorine-containing elastomer composition of the present invention thus obtained, the crosslinking agent (C) is uniformly dispersed in the fluorine-containing elastomer (B). As a result, the vulcanization rate of the fluorine-containing elastomer composition And the compression cracking resistance of the cross-linked molded product can be improved.

  Next, each component will be described.

  The organic solvent (A) to be mixed in the mixing step (I) is not particularly limited as long as it can dissolve or disperse the fluorine-containing elastomer (B) and the crosslinking agent (C).

  Specifically, for example, ketone solvents such as acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK); N, N-dimethylformamide (DMF), N, N-dimethylacetamide (DMAc), N-methyl-2 Amide solvents such as pyrrolidone (NMP); ester solvents such as ethyl acetate, butyl acetate, and ethyl lactate; ether solvents such as tetrahydrofuran (THF), tetramethyltetrahydrofuran (4Me-THF), ethyl cellosolve; sulfolane, methyl Examples include sulfolane solvents such as sulfolane; carbonate solvents such as propylene carbonate and diethyl carbonate.

  Of these, ketone solvents, ether solvents, and sulfolane solvents are preferred from the viewpoint of good solubility or uniform dispersibility of the crosslinking agent, and acetone, methyl ethyl ketone, tetrahydrofuran, and sulfolane are particularly preferred. To more preferable.

  The amount of the organic solvent (A) used varies greatly depending on the amount of the crosslinking agent, the amount of the elastomer used, etc. From the viewpoint of further improving the dispersibility of the crosslinking agent, it is 0.1 mass relative to 100 parts by mass of the elastomer. Part or more, more preferably 1.0 part by mass or more. Although an upper limit is not specifically limited, 500 mass parts with respect to 100 mass parts of an elastomer, Furthermore, 100 mass parts is employable.

  The fluorine-containing elastomer (B) may be a non-perfluoro fluorine-containing elastomer (B1) or a perfluoro elastomer (B2) as long as it is an elastomer containing fluorine atoms.

The non-perfluoro fluorine-containing elastomer (B1) is not particularly limited, but as a crosslinking site capable of crosslinking reaction with the crosslinking agent (C), a cyano group (—CN group), a hydroxyl group (—OH), A carboxyl group (—COOH group), an alkoxycarbonyl group (—COOR ⁵ group (R ⁵ is a monovalent organic group)), an acid halide group (—COX ¹ group (X ¹ is a halogen atom, Are preferably at least one functional group capable of undergoing a crosslinking reaction with a crosslinking agent (C) such as an iodine atom, a chlorine atom or a bromine atom) at least one of the main chain and the side chain terminal. . Among these, a cyano group, a carboxyl group, an alkoxycarbonyl group, and an acid halide group are more preferable from the viewpoint of good crosslinking reactivity, and a cyano group is particularly preferable. Moreover, a carboxyl group and an alkoxycarbonyl group are more preferable from the viewpoint of easy production.

The monovalent organic group R ⁵ is not limited, and examples thereof include an aliphatic hydrocarbon group, a phenyl group, and a benzyl group. Specifically, for example, a lower alkyl group having 1 to 10 carbon atoms, particularly 1 to 6 carbon atoms such as —CH ₃ , —C ₂ H ₅ , —C ₃ H _7, etc .; —CF ₃ , —C ₂ F ₅ , —CH A fluorine-containing lower alkyl group having 1 to 10 carbon atoms, particularly 1 to 6 carbon atoms, such as ₂ F, —CH ₂ CF ₃ , —CH ₂ C ₂ F ₅ ; phenyl group; benzyl group; —C ₆ F ₅ , —CH A phenyl group or a benzyl group in which 1 to 5 hydrogen atoms are substituted with a fluorine atom such as ₂ C ₆ F ₅ ; -C ₆ H _5-m (CF ₃ ) _m , —CH ₂ C ₆ H _5-m ( And a phenyl group or a benzyl group in which 1 to 5 hydrogen atoms are substituted with —CF ₃ such as CF ₃ ) _m (m is an integer of 1 to 5).

  Examples of the non-perfluoro fluorine-containing elastomer (B1) include, for example, a non-perfluoro fluorine-containing elastomer (b1), a non-perfluoro thermoplastic fluorine-containing elastomer (b2), and these non-perfluoro fluorine-containing elastomers (b1), ( Examples thereof include a rubber composition (b3) comprising b2), and among these, a non-perfluorofluorinated elastomer (b1) is preferred.

  The non-perfluoro fluorine-containing elastomer (b1) is not particularly limited, but it is relatively inexpensive, has good polymerizability, and is excellent in heat resistance, cold resistance, and chemical resistance of the resulting compound. It preferably comprises a vinylidene chloride (VdF) unit and / or a tetrafluoroethylene (TFE) unit and at least one other monomer unit copolymerizable therewith.

  Examples of at least one other monomer include hexafluoropropylene (HFP), perfluoro (alkyl vinyl ether) (PAVE), chlorotrifluoroethylene (CTFE), fluoroalkyl vinyl ether, trifluoroethylene, trifluoropropylene, and tetrafluoro. Fluorinated monomers such as propylene, pentafluoropropylene, trifluorobutene, tetrafluoroisobutene, vinyl fluoride, and iodine-containing fluorinated vinyl ethers; non-fluorinated monomers such as ethylene (Et), propylene (Pr), and alkyl vinyl ethers Of these fluorinated monomers and non-fluorinated monomers, one or a combination of two or more can be used.

The PAVE has the formula (5):
_{CF 2 = CFO (CF 2 CFY} 1 O) p - (CF 2 CF 2 CF 2 O) q -Rf 2 (5)
(Wherein Y ¹ is a fluorine atom or —CF ₃ ; Rf ² is a perfluoroalkyl group having 1 to 5 carbon atoms; p is an integer of 0 to 5; q is an integer of 0 to 5)
These can be used alone or in combination of two or more. Among the monomers represented by the formula (5), perfluoro (methyl vinyl ether) is particularly preferable from the viewpoint of good cold resistance.

  Specifically, from the viewpoint of good compatibility with the crosslinking agent (C), VdF / HFP copolymer, VdF / HFP / TFE copolymer, VdF / CTFE copolymer, VdF / CTFE / TFE copolymer weight. Polymer, VdF / PAVE copolymer, VdF / TFE / PAVE copolymer, VdF / HFP / PAVE copolymer, VdF / HFP / TFE / PAVE copolymer, VdF / TFE / Pr copolymer, Et / HFP A copolymer and a VdF / Et / HFP copolymer are preferable, and a VdF / HFP copolymer and a VdF / HFP / TFE copolymer are particularly preferable.

  The VdF / HFP copolymer preferably has a VdF / HFP composition of 45 to 85/15 to 55 mol%, more preferably 50 to 80/20 to 50 mol%, and still more preferably, 60-80 / 20-40 mol%.

  The VdF / HFP / TFE copolymer preferably has a VdF / HFP / TFE composition of 40 to 80/10 to 35/10 to 25 mol%.

  The VdF / PAVE copolymer preferably has a VdF / PAVE composition of 65 to 90/10 to 35 mol%.

  As a VdF / TFE / PAVE copolymer, the composition of VdF / TFE / PAVE is preferably 40 to 80/3 to 40/15 to 35 mol%.

  The VdF / HFP / PAVE copolymer preferably has a VdF / HFP / PAVE composition of 65 to 90/3 to 25/3 to 25 mol%.

  As VdF / HFP / TFE / PAVE copolymer, the composition of VdF / HFP / TFE / PAVE is preferably 40 to 90/0 to 25/0 to 40/3 to 35, preferably 40 to 80/3 to 25 More preferred are those of / 3 to 40/3 to 25 mol%.

  From the viewpoint of amine resistance and the like, VdF / TFE / Pr copolymer, Et / HFP copolymer, and Et / HFP / TFE copolymer are preferable.

  The VdF / TFE / Pr copolymer preferably has a composition of VdF / TFE / Pr of 30 to 90/5 to 50 mol / 5 to 40 mol%, and preferably 30 to 65/25 to 45/10 to 35. Mole% is more preferable.

  The Et / HFP copolymer preferably has an Et / HFP composition of 35 to 80/20 to 65 mol%, more preferably 40 to 75/25 to 60 mol%.

  The Et / HFP / TFE copolymer preferably has an Et / HFP / TFE composition of 35 to 75/50 to 25/15 to 0 mol%, and 45 to 75/45 to 25/10 to 0 mol. % Is more preferable.

  From the viewpoint of cold resistance, a TFE / VdF / PAVE copolymer and a CTFE / VdF / PAVE copolymer are preferable.

  In total, VdF / HFP copolymer, VdF / TFE / HFP copolymer, and VdF / TFE / PAVE copolymer are preferable.

  A crosslinking site capable of undergoing a crosslinking reaction with the crosslinking agent (C) described later may be introduced into the fluorine-containing elastomer by a polymer reaction, but is exemplified above as the non-perfluoro fluorine-containing elastomer (b1). It is preferable to use a monomer that gives a crosslinking site as another monomer in the copolymer because it is easy to produce. The monomer giving a crosslinking site is preferably 0.1 mol% or more, more preferably 0, based on the total amount of monomers (including the monomer giving the crosslinking site) constituting the non-perfluoro fluorine-containing elastomer (b1). .3 mol% or more, preferably 5 mol% or less, more preferably 2 mol% or less.

（Ｒ⁵は上記と同じ）
で示される基を有するものが例示できる。 Monomers that give a crosslinking site have an ethylenically unsaturated bond, and cyano groups (—CN groups), hydroxyl groups (—OH groups), carboxyl groups (—COOH groups), alkoxycarbonyl groups ( -COOR ⁵ group (R ⁵ is the same as above)), acid halide group (-COX ¹ group (X ¹ is the same as above)) or

(R ⁵ is the same as above)
What has group shown by can be illustrated.

As the monomer for introducing the crosslinkable site, both a chain compound and a cyclic compound can be used, but the monomer is preferably a chain compound from the viewpoint of good polymerizability. Among the chain compounds, particularly, the formula (6):
CY ² Y ³ = CY ⁴ (O) _k (R ⁶ ) ₁ −X ² (6)
Wherein Y ^{2 to} Y ⁴ are the same or different and are a hydrogen atom, a halogen atom, —CH ₃ or —CF ₃ ; R ⁶ is a divalent organic group; l is 0 or 1; And 0 is 1 when l is 1, and X ² is any of the above crosslinkable functional groups)
Is preferred.

Particularly, examples of the monomer for introducing a suitable crosslinkable site include the following compounds.
_{CH 2 = CH- (CF 2)} l -X 2 (7)
(Wherein l is an integer from 2 to 8)
CY ⁵ ₂ = CY ⁵ (CF ₂ ) _l -X ² (8)
(Wherein Y ⁵ is a hydrogen atom or a fluorine atom, and l is an integer of 1 to 8)
^{_{CF 2 = CFCF 2 Rf 3 -X}} 2 (9)
(In the formula, Rf ³ is — (OCF ₂ ) ₁ — or — (OCF (CF ₃ )) ₁ — (l is an integer of 0 to 5))
CF ₂ = CFCF ₂ (OCF (CF ₃ ) CF ₂ ) _k
(OCH ₂ CF ₂ CF ₂ ) _l OCH ₂ CF ₂ -X ² (10)
(In the formula, k is an integer of 0 to 5; l is an integer of 0 to 5)
CF ₂ = CFCF ₂ (OCH ₂ CF ₂ CF ₂ ) _k
(OCF (CF ₃ ) CF ₂ ) _l OCF (CF ₃ ) -X ² (11)
(In the formula, k is an integer of 0 to 5; l is an integer of 0 to 5)
_{CF 2 = CF (OCF 2 CF} (CF 3)) k O (CF 2) l -X 2 (12)
(Wherein k is an integer of 0 to 5; l is an integer of 1 to 8)
_{CF 2 = CF (OCF 2 CF} (CF 3)) k -X 2 (13)
(Wherein k is an integer of 1 to 5)
CF ₂ = CFOCF ₂ (CF (CF ₃ ) OCF ₂ ) _l CF (−X ¹ ) CF ₃ (14)
(Wherein l is an integer of 1 to 4)
_{CF 2 = CFO (CF 2)} l OCF (CF 3) -X 2 (15)
(Wherein l is an integer of 2 to 5)
_{CF 2 = CFO (CF 2)} l - (C 6 H 4) -X 2 (16)
(Wherein l is an integer from 1 to 6)
CF ₂ = CF (OCF ₂ CF (CF ₃ )) _l OCF ₂ CF (CF ₃ ) -X ² (17)
(Wherein l is an integer of 1 to 2)
_{CH 2 = CFCF 2 O (CF} (CF 3) CF 2 O) l CF (CF 3) -X 2 (18)
(In the formula, l is an integer of 0 to 5)
_{CF 2 = CFO (CF 2 CF} (CF 3) O) k (CF 2) l -X 2 (19)
(In the formula, k is an integer of 0 to 5; l is an integer of 1 to 3)
_{CH 2 = CFCF 2 OCF (CF} 3) OCF (CF 3) -X 2 (20)
_{CH 2 = CFCF 2 OCH 2 CF} 2 -X 2 (21)
_{CF 2 = CFO (CF 2 CF} (CF 3) O) k CF 2 CF (CF 3) -X 2 (22)
(Wherein k is an integer of 0 or more)
_{CF 2 = CFOCF (CF 3)} CF 2 O (CF 2) l -X 2 (23)
(In the formula, l is an integer of 1 or more)
_{CF 2 = CFOCF 2 OCF 2 CF} (CF 3) OCF 2 -X 2 (24)
_{CF 2 = CF- (CF 2 C} (CF 3) F) l -X 2 (25)
(Wherein l is an integer of 1 to 5)
^{_{CF 2 = CFO- (CFY 6)}} l -X 2 (26)
(In the formula, Y ⁶ is —F or —CF ₃ ; l is an integer of 1 to 10)
_{CF 2 = CFO- (CF 2 CFY} 7 O) k - (CF 2) l -X 2 (27)
(Wherein Y ⁷ is —F or —CF ₃ ; k is an integer of 1 to 10; l is an integer of 1 to 3)
_{CH 2 = CFCF 2 O- (CF} (CF 3) CF 2 O) l -CF (CF 3) -X 2 (28)
(Wherein l is an integer from 0 to 10)
_{CF 2 = CFCF 2 O- (CF} (CF 3) CF 2 O) l -CF (CF 3) -X 2 (29)
(Wherein l is an integer from 1 to 10)
(In formulas (7) to (29), X ² is any one of the crosslinkable functional groups)

  Moreover, it is preferable that non-perfluoro fluorine-containing elastomer (b1) contains 0.1-5 mol% of said crosslinkable functional groups in a side chain, and it is more preferable to contain 0.3-2 mol%. If it is less than 0.1 mol%, a crosslinked molded product obtained by a crosslinking reaction with a crosslinking agent (C) described later tends to fail to obtain sufficient mechanical strength, heat resistance and chemical resistance. If it exceeds%, the cross-linked molded product tends to be too hard and lose its flexibility.

  The non-perfluoro fluorine-containing elastomer (b1) used in the present invention can be produced by a conventional method, and can be produced by a polymerization method such as an emulsion polymerization method, a suspension polymerization method, or a solution polymerization method. What is necessary is just to determine suitably polymerization conditions, such as temperature at the time of superposition | polymerization, time, according to the kind of monomer, and the target elastomer. You may add an emulsifier, a molecular weight modifier, a pH adjuster, etc. The molecular weight modifier may be added all at once in the initial stage, or may be added continuously or dividedly.

  Examples of the perfluoroelastomer (B2) include a TFE / PAVE copolymer.

  As the fluorine-containing elastomer (B), a non-perfluoro fluorine-containing elastomer (B1) is preferable from the viewpoint of good solubility in an organic solvent.

（式中、Ｒ¹は−ＮＨ₂、−ＮＨＲ²、−ＯＨまたは−ＳＨであり、Ｒ²はフッ素原子または１価の有機基である）
で示される架橋性反応基を少なくとも２個有する、ビスジアミノフェニル系化合物、ビスアミノフェノール系化合物またはビスアミノチオフェノール系化合物（架橋剤（Ｃ１））、
式（２）：

で示されるビスアミドラゾン系化合物（架橋剤（Ｃ２））、
式（３）：

（式中、Ｒｆ¹は炭素数１〜１０のパーフルオロアルキレン基である）
で示されるビスアミドラゾン系化合物（架橋剤（Ｃ３））、および
式（４）：

（式中、ｎは１〜１０の整数である）
で示されるビスアミドキシム系化合物（架橋剤（Ｃ４））
よりなる群から選ばれる少なくとも１種の架橋剤である。 As a crosslinking agent (C),
Formula (1):

(Wherein R ¹ is —NH ₂ , —NHR ² , —OH or —SH, and R ² is a fluorine atom or a monovalent organic group)
A bisdiaminophenyl compound, a bisaminophenol compound or a bisaminothiophenol compound (crosslinking agent (C1)) having at least two crosslinkable reactive groups represented by
Formula (2):

A bisamidrazone compound represented by (crosslinking agent (C2)),
Formula (3):

(Wherein Rf ¹ is a C 1-10 perfluoroalkylene group)
And a bisamidrazone compound (crosslinking agent (C3)) represented by formula (4):

(Where n is an integer from 1 to 10)
Bisamidoxime compound (crosslinking agent (C4))
At least one crosslinking agent selected from the group consisting of:

  Among these, as the crosslinking agent (C), a crosslinking agent (C1) having at least two crosslinking reactive groups represented by the formula (1) is preferable.

  The crosslinking agent (C1) having at least two crosslinkable reactive groups represented by the formula (1) preferably has 2 to 3 crosslinkable reactive groups represented by the formula (1), and more preferably has two. Is. If the number of crosslinkable reactive groups represented by formula (1) is less than 2, crosslinking cannot be performed.

（式中、Ｒ¹は前記と同じ、Ｒ⁷は、−ＳＯ₂−、−Ｏ−、−ＣＯ−、炭素数１〜６のアルキレン基、炭素数１〜１０のパーフルオロアルキレン基、単結合手、または

で示される基である）
で示される架橋剤が、合成が容易な点から好ましい。 As the crosslinking agent (C1), the formula (30) having two crosslinkable reactive groups represented by the formula (1):

(Wherein R ¹ is the same as above, R ⁷ is —SO ₂ —, —O—, —CO—, an alkylene group having 1 to 6 carbon atoms, a perfluoroalkylene group having 1 to 10 carbon atoms, and a single bond. Hand, or

Is a group represented by
Is preferable from the viewpoint of easy synthesis.

などがあげられる。 Preferable specific examples of the alkylene group having 1 to 6 carbon atoms include a methylene group, an ethylene group, a propylene group, a butylene group, a pentylene group, a hexylene group, and the like. As the perfluoroalkylene group having 1 to 10 carbon atoms, Is

Etc.

  These compounds are known as examples of bisdiaminophenyl compounds in JP-B-2-59177 and JP-A-8-120146.

（式中、Ｒ⁸は、同じかまたは異なり、いずれも水素原子、炭素数１〜１０のアルキル基；フッ素原子を含有する炭素数１〜１０のアルキル基；フェニル基；ベンジル基；フッ素原子および／または−ＣＦ₃で１〜５個の水素原子が置換されたフェニル基またはベンジル基である）
で示される化合物である。 Among these, as a more preferable crosslinking agent (C1), the formula (31):

(Wherein R ⁸ is the same or different, and both are hydrogen atoms, alkyl groups having 1 to 10 carbon atoms; alkyl groups having 1 to 10 carbon atoms containing fluorine atoms; phenyl groups; benzyl groups; fluorine atoms and (Or phenyl group or benzyl group in which 1 to 5 hydrogen atoms are substituted with —CF ₃ )
It is a compound shown by these.

  Specific examples include, but are not limited to, for example, 2,2-bis (3,4-diaminophenyl) hexafluoropropane, 2,2-bis [3-amino-4- (N-methylamino) phenyl] hexa Fluoropropane, 2,2-bis [3-amino-4- (N-ethylamino) phenyl] hexafluoropropane, 2,2-bis [3-amino-4- (N-propylamino) phenyl] hexafluoropropane 2,2-bis [3-amino-4- (N-phenylamino) phenyl] hexafluoropropane, 2,2-bis [3-amino-4- (N-perfluorophenylamino) phenyl] hexafluoropropane 2,2-bis [3-amino-4- (N-benzylamino) phenyl] hexafluoropropane and the like. Among these, 2,2-bis (3,4-diaminophenyl) hexafluoropropane is more preferable from the viewpoint of excellent heat resistance and particularly good crosslinking reactivity.

  These bisaminophenol-based crosslinking agents, bisaminothiophenol-based crosslinking agents, bisdiaminophenyl-based crosslinking agents, bisamidrazone-based crosslinking agents, bisamidoxime-based crosslinking agents and the like are included in the fluorine-containing elastomer (B) of the present invention. It reacts with a crosslinkable functional group such as a cyano group, a carboxyl group, an alkoxycarbonyl group, or an acid halide group to form an oxazole ring, a thiazole ring, or an imidazole ring to give a crosslinked product.

  The cross-linking agent (C) described above is excellent in mechanical strength, heat resistance, chemical resistance, and cold resistance, and particularly provides a cross-linked product having a good balance between heat resistance and cold resistance.

  The addition amount of the crosslinking agent (C) is preferably 0.1 to 20 parts by mass and more preferably 0.5 to 10 parts by mass with respect to 100 parts by mass of the fluorine-containing elastomer (B). When the cross-linking agent (C) is less than 0.1 parts by mass, there is a tendency that practically sufficient mechanical strength, heat resistance and chemical resistance cannot be obtained. In addition, the crosslinked product tends to be hard and not flexible.

  In the present invention, particularly in a field where high purity and non-staining properties are not required, usual additives blended in the fluorine-containing elastomer composition as necessary, for example, filler (D), processing aid, plasticizer, coloring Agents, stabilizers, adhesion assistants, and the like can be blended, and one or more conventional crosslinking agents and crosslinking assistants different from those described above may be blended.

  The filler (D) improves physical properties such as tensile strength, modulus, and hardness of the crosslinked product, and can be added as necessary in the present invention.

  Examples of the filler (D) include carbon black, talc, silicic acid, silicic acid compound, calcium carbonate, barium sulfate, clay, high styrene resin, phenol resin, and coumarone resin. Among them, carbon black generally used includes thermal black, bituminous coal filler, furnace black, channel black and the like. Among these, a bituminous coal filler is preferable from the viewpoint of resistance to compression set, and a mixture of bituminous coal filler and thermal black is preferable from the viewpoint of mechanical properties.

  The addition amount of the filler (D) is preferably 10 to 50 parts by mass with respect to 100 parts by mass of the fluorine-containing elastomer (B), from the viewpoint of good mechanical properties of the molded product, and 15 to 45 parts by mass. It is more preferable from the viewpoint that the balance between the tensile strength and the elongation of the molded product obtained to be a part is even better.

  Moreover, when using the mixture of a bituminous coal filler and thermal black, it is preferable that the mixing weight ratio (bituminous coal filler / thermal black) is 9 / 95-80 / 20, and it is 30 / 70-70 / 30. More preferred. When it is out of the above range, deterioration in compression set resistance and reduction in compression crack resistance are observed.

  In the present invention, an inorganic substance may be added as the crosslinking accelerator (E).

  As the inorganic substance that can be used as the crosslinking accelerator (E), inorganic oxides, inorganic nitrides, and carbon materials are preferable, and among them, a compound having an adsorptivity to water and alcohol, a compound having a base point, and the like are more preferable. .

  Examples of the compound having an adsorptivity to water and alcohol include molecular sieves, magnesium sulfate, sodium sulfate, activated carbon, and mesoporous silica. Among these, molecular sieves are particularly preferable from the viewpoint of improving the crosslinking rate and resistance to compression set.

Examples of the compound having a base point include (1) alkali metals, alkaline earth metals and oxides thereof, (2) silica, alumina, carbon, activated carbon containing alkali metals, alkaline earth metals and oxides thereof, (3) Inorganic nitrides such as silicon nitride (Si ₃ N ₄ ) and AlN, and (4) silica, alumina, carbon, activated carbon and the like having amine functional groups on the surface. Among these, (2) silica, alumina, carbon, activated carbon containing alkali metals, alkaline earth metals and oxides thereof, (3) inorganic nitrides such as silicon nitride (Si ₃ N ₄ ) and AlN, (4) Silica, alumina, carbon, activated carbon and the like having an amine functional group on the surface are more preferred, and (3) inorganic nitrides such as silicon nitride (Si ₃ N ₄ ) and AlN are particularly preferred.

  Moreover, what carried these on silica, alumina, carbon, etc. can be used suitably.

  Specific examples include magnesium oxide, aluminum oxide, sodium oxide, zinc oxide, hydrotalcite, zonotlite, wollastonite, talc, attapulgite, bentonite, zeolite, clay, pyrophyllite, selenite and the like. These compounds include Carplex # 1120 (manufactured by Degussa Japan), Carplex # 100 (manufactured by Degussa Japan), Toxeal Gu (manufactured by Tokuyama Corporation), Nip Seal ER (manufactured by Nippon Silica Industry Co., Ltd.), Nip Seal NA (Nippon Silica Industry Co., Ltd.), nip seal g300 (Nihon Silica Industry Co., Ltd.), etc. can be used.

  The amount of the inorganic substance used as the crosslinking accelerator is preferably 0.1 parts by mass or more, more preferably 0.5 parts by mass or more, with respect to 100 parts by mass of the fluorine-containing elastomer (B). The amount is more preferably at least 5 parts by mass, and particularly preferably at least 5 parts by mass. Moreover, as an upper limit, it is preferable that it is 50 mass parts or less, and it is more preferable that it is 30 mass parts or less. If the amount is less than 0.1 parts by mass, the effect of adding an inorganic substance tends to be insufficient, and if it exceeds 50 parts by mass, the hardness tends to increase and the moldability tends to be inferior.

（式中、Ｒ¹は−ＮＨ₂、−ＮＨＲ²、−ＯＨまたは−ＳＨであり、Ｒ²はフッ素原子または１価の有機基である）
で示される架橋性反応基を少なくとも２個含む架橋剤、
（Ｃ２）式（２）：

で示される架橋剤、
（Ｃ３）式（３）：

（式中、Ｒｆ¹は炭素数１〜１０のパーフルオロアルキレン基である）
で示される架橋剤、および
（Ｃ４）式（４）：

（式中、ｎは１〜１０の整数である）
で示される架橋剤
よりなる群から選ばれる少なくとも１種の架橋剤である組成物にも関する。 The present invention is also a composition comprising an organic solvent (A) and a crosslinking agent (C), wherein the crosslinking agent (C) is
(C1) Formula (1):

(Wherein R ¹ is —NH ₂ , —NHR ² , —OH or —SH, and R ² is a fluorine atom or a monovalent organic group)
A crosslinking agent comprising at least two crosslinkable reactive groups represented by:
(C2) Formula (2):

A cross-linking agent represented by
(C3) Formula (3):

(Wherein Rf ¹ is a C 1-10 perfluoroalkylene group)
And (C4) Formula (4):

(Where n is an integer from 1 to 10)
The composition which is at least 1 sort (s) of crosslinking agent chosen from the group which consists of a crosslinking agent shown by these is also related.

  When this crosslinking agent composition is used in the mixing step (I), the dispersibility of the crosslinking agent (C) can be further enhanced. Moreover, this crosslinking agent composition may further contain a fluorine-containing elastomer (B).

  The organic solvent (A) may be any solvent that can dissolve or uniformly disperse the crosslinking agent (C). Particularly, the above-mentioned ketone solvent, amide solvent, ester solvent, ether solvent, sulfolane solvent and It is preferably at least one selected from the group consisting of carbonate solvents from the viewpoint of good solubility or uniform dispersibility of the crosslinking agent. Specific examples and preferred specific examples are also the same as described above.

  In the cross-linking agent composition, the lower limit of the amount of the cross-linking agent (C) is not particularly limited, but is, for example, about 0.1 parts by mass from the viewpoint of suppressing the energy cost of the subsequent removal of the organic solvent. The upper limit is not particularly limited as long as it can be uniformly dispersed or dissolved, but for example, 100 parts by mass, and more preferably 50 parts by mass with respect to 100 parts by mass of the organic solvent (A).

  In particular, a combination of a ketone solvent or a sulfolane solvent and a crosslinking agent (C1) is preferable from the viewpoint of good solubility of the crosslinking agent in an organic solvent.

  Next, a method for producing the fluorine-containing elastomer molded product of the present invention will be described.

  The method for producing a fluorine-containing elastomer molded product of the present invention is a cross-linked molding in which the fluorine-containing elastomer composition obtained through the mixing step (I) is cross-linked to form a cross-linked molded product according to the above-described method for producing a composition. Including step (III).

  In addition, you may perform a drying process (II) between mixing process (I) and bridge | crosslinking shaping | molding process (III).

  In the present invention, the crosslinking conditions are not particularly limited, and can be carried out under the crosslinking conditions of ordinary fluorine-containing elastomers. For example, in the case of performing oxazole crosslinking, press crosslinking is performed by placing in a mold and holding under pressure at 120 to 250 ° C. for 1 to 60 minutes, followed by 0 to 48 hours in an oven at 120 to 320 ° C. When oven crosslinking is performed by holding, a crosslinked product can be obtained.

  In addition, when imidazole crosslinking is performed, it is most suitable for carboxyl-containing polymers having carboxyl groups other than those at the ends, and crosslinking having good physical properties at a relatively low crosslinking temperature (for example, 150 to 230 ° C., preferably 170 to 200 ° C.). Give things.

  The fluorine-containing elastomer molded product of the present invention thus obtained is excellent in compression set resistance and compression crack resistance.

  The fluorine-containing elastomer molded product of the present invention is useful as various molded products in various fields, and is useful as various molded products in the following fields. Among them, it is useful for hose materials, particularly transport equipment (automobiles, etc.). Useful as a hose material around engines that are exposed to high temperature environments. Examples include turbocharger hoses and intercoolers.

  As applications other than automotive applications, preferred fields are semiconductor manufacturing equipment, liquid crystal panel manufacturing equipment, plasma panel manufacturing equipment, plasma address liquid crystal panels, field emission display panels, semiconductor related fields such as solar cell substrates, aircraft fields, rocket fields, Ships, chemicals such as plants, chemicals such as pharmaceuticals, photographic fields such as developing machines, printing fields such as printing machines, coating fields such as coating equipment, food plant equipment fields, nuclear power plant equipment fields, iron plate processing equipment The steel field, general industrial field, fuel cell field, electronic component field, etc. can be raised.

  Next, the present invention will be described with reference to examples, but the present invention is not limited to such examples.

Measurement Evaluation Method (1) NMR
Apparatus: AC-300 manufactured by BRUKER
Measurement condition:
¹⁹ F-NMR: 282 MHz (trifluoromethylbenzene = −62.3 ppm)
¹ H-MNR: 300 MHz (trifluoromethylbenzene = 7.51 ppm)
(2) Infrared spectroscopic analysis (IR)
Measured at room temperature with a Perkin Elmer Fourier transform infrared spectrophotometer 1760X.
(3) Mooney viscosity Measured according to ASTM-D1646 and JIS K6300.
Measuring equipment: ALPHA TECHNOLOGIES MV2000E type rotor rotation speed: 2rpm
Measurement temperature: 121 ° C
(4) Vulcanizability Measure the vulcanization degree and vulcanization speed with a curast meter.
Measuring device: JSR Co., Ltd. Curlastometer type II (5) compression set Measured in accordance with JIS K6301.
The compression set of the O-ring (AS-568A-214) after 260 ° C. and 70 hours is calculated.
(6) Compression crack resistance Measured according to JIS K6301.
Five O-rings (AS-568A-214) are used, and the compression rate is 40%. The number of occurrences of O-ring cracks after 2 hours at 280 ° C. is determined.

Production Example 1 (Synthesis of CNVE unit-containing elastomer)
A stainless steel autoclave having an internal volume of 6 liters having no ignition source, 3.0 liters of pure water, 6.0 g of C ₅ F ₁₁ COONH ₄ as an emulsifier and CH ₂ ═CFCF ₂ OCF (CF ₃ ) CF ₂ OCF (CF ₃ ) COONH ₄ 0.15 g, disodium hydrogen phosphate 3.5 g, sodium hydroxide 0.6 g were charged, and the system was sufficiently replaced with nitrogen gas and degassed, and then stirred at 600 rpm. The temperature was raised to 80 ° C., and a mixed gas of vinylidene fluoride (VdF), tetrafluoroethylene (TFE), and hexafluoropropylene (HFP) (VdF / TFE / HFP = 19/11/70 molar ratio) with an internal pressure of 1 It charged so that it might become 0.5MPa * G. Then, 1.8 g / 2 ml of ammonium persulfate (APS) aqueous solution, CF ₂ = CFOCF ₂ CF (CF ₃ ) OCF ₂ CF ₂ CN (CNVE) was injected under pressure of 1.8 g of nitrogen pressure to initiate the reaction.

  When the internal pressure dropped to 1.48 MPa · G due to the progress of the polymerization, 0.2 g of diethyl malonate was injected under nitrogen pressure. Subsequently, a mixed gas of VdF, TFE, and HFP (VdF / TFE / HFP = 50/20/30 molar ratio) was injected so that the pressure became 1.52 MPa · G. Thereafter, as the reaction proceeds, a mixed gas of VdF, TFE, and HFP is injected, and the pressure is increased and decreased repeatedly between 1.48 and 1.52 MPa · G, and 15 g of CNVE and 1.2 g of sodium hydroxide are added. Press-fitted with nitrogen pressure.

  10 hours after the start of the polymerization reaction, when the total charge amount of VdF, TFE, and HFP reaches 1000 g, the autoclave is cooled, the unreacted monomer is released, and the aqueous dispersion having a solid content concentration of 25.5% by mass 3984 g was obtained. The pH of the aqueous dispersion was 5.1.

  2000 g of this aqueous dispersion was slowly added to 2000 g of magnesium sulfate aqueous solution with stirring. After the addition, the mixture was stirred for 1 minute, and then the coagulated product was separated by filtration. After that, washing with water and filtration were repeated three more times, followed by washing with methanol, followed by vacuum drying at room temperature for 48 hours to obtain 499 g of a polymer. .

As a result of NMR analysis, the monomer unit composition of this polymer was VdF / TFE / HFP / CNVE (= 50.7 / 19.2 / 29.7 / 0.4 mol%). Moreover, the characteristic absorption of the nitrile group was recognized in the vicinity of 2169 cm ⁻¹ by infrared spectroscopic analysis. Further, the Mooney viscosity (ML _{1 + 10} (121 ° C.)) of this polymer was 93.

Example 1
Mixing step (I)
1.8 parts by mass of 2,2-bis (3-amino-4-hydroxyphenyl) hexafluoropropane (crosslinking agent OH-AF) is dissolved in 2 parts by mass of acetone to prepare a premixed mixture Ia-1 (crosslinking agent composition). Was prepared.

  Next, 100 parts by mass of the CNVE unit-containing elastomer obtained in Production Example 1 and 20 parts by mass of thermal black (MT-C, manufactured by Cancarb Co.) were kneaded with an open roll while adding the preliminary mixture Ia-1. .

Cross-linking molding process (III)
This cross-linked fluorine-containing elastomer composition was pressed at 180 ° C. for 10 minutes to perform cross-linking, and further subjected to oven cross-linking at 200 ° C. for 2 hours, 260 ° C. for 5 hours, and then 290 ° C. for 18 hours to obtain a thickness of 2 mm. A crosslinked product was produced.

  Moreover, the test sample of O-ring (AS-568A-214) was produced on the same bridge | crosslinking conditions.

Evaluation Vulcanizability of the fluorine-containing elastomer composition for crosslinking, compression set of the O-ring, and resistance to compression cracking were examined. The results are shown in Table 1.

Example 2
Mixing step (I)
1.8 parts by mass of 2,2-bis (3-amino-4-hydroxyphenyl) hexafluoropropane (crosslinking agent OH-AF) is dissolved in 2 parts by mass of sulfolane and premixed Ia-1 (crosslinking agent composition) Was prepared.

  Next, 100 parts by mass of the CNVE unit-containing elastomer obtained in Production Example 1 and 20 parts by mass of thermal black (MT-C) were kneaded with an open roll while adding the preliminary mixture Ia-1.

Cross-linking molding process (III)
The cross-linked fluorine-containing elastomer composition was pressed at 180 ° C. for 30 minutes to perform cross-linking, and then subjected to oven cross-linking for 2 hours at 200 ° C., 5 hours at 260 ° C., then 18 hours at 290 ° C., and a thickness of 2 mm. A crosslinked product was produced.

  Moreover, the test sample of O-ring (AS-568A-214) was produced on the same bridge | crosslinking conditions.

Evaluation Vulcanizability of the fluorine-containing elastomer composition for crosslinking, compression set of the O-ring, and resistance to compression cracking were examined. The results are shown in Table 1.

Comparative Example 1
Mixing step (I)
Mass ratio of 2,2-bis (3-amino-4-hydroxyphenyl) hexafluoropropane (crosslinking agent OH-AF) and thermal black (MT-C) to the CNVE unit-containing elastomer obtained in Production Example 1 At 100 / 0.8 / 20, kneading was conducted with an open roll without using an organic solvent to prepare a comparative fluorine-containing elastomer composition for crosslinking. Since no organic solvent was used, the drying step (II) was not performed.

Cross-linking molding process (III)
The cross-linked fluorine-containing elastomer composition was pressed at 180 ° C. for 30 minutes to perform cross-linking, and then subjected to oven cross-linking for 2 hours at 200 ° C., 5 hours at 260 ° C., then 18 hours at 290 ° C., and a thickness of 2 mm. A crosslinked product was produced.

  Moreover, the test sample of O-ring (AS-568A-214) was produced on the same bridge | crosslinking conditions.

Evaluation Vulcanizability of the fluorine-containing elastomer composition for crosslinking, compression set of the O-ring, and resistance to compression cracking were examined. The results are shown in Table 1.

  As can be seen from Table 1, when mixed using an organic solvent, the crosslinking rate (vulcanization time) can be greatly shortened, and the resulting crosslinked molded article has improved compression set and resistance to compression cracking. Has also greatly improved.

Claims (14)

The manufacturing method of the fluorine-containing elastomer composition for bridge | crosslinking including the process (I) which mixes an organic solvent (A), a fluorine-containing elastomer (B), and a crosslinking agent (C). The manufacturing method of the composition of Claim 1 including process (II) which dries the obtained mixture. The manufacturing method of the composition of Claim 1 or 2 which mixes a filler (D) further in mixing process (I). In the mixing step (I), the organic solvent (A) and the crosslinking agent (C) are mixed to prepare the preliminary mixture (Ia-1), and then the preliminary mixture (Ia-1) and the fluorine-containing elastomer (B) are mixed. The manufacturing method of the composition in any one of Claims 1-3 knead | mixed. The method for producing a composition according to any one of claims 1 to 4, wherein the fluorine-containing elastomer (B) is a non-perfluoro fluorine-containing elastomer (B1). The production of the composition according to claim 5, wherein the non-perfluoro fluorine-containing elastomer (B1) comprises vinylidene fluoride units and / or tetrafluoroethylene units and at least one other monomer unit copolymerizable therewith. Method. Non-perfluoro fluorine-containing elastomer (B1)
(1) vinylidene fluoride / hexafluoropropylene copolymer,
The method for producing a composition according to claim 6, which is (2) a vinylidene fluoride / tetrafluoroethylene / hexafluoropropylene copolymer or (3) a tetrafluoroethylene / vinylidene fluoride / perfluoroalkyl vinyl ether copolymer. Crosslinking agent (C)
(C1) Formula (1):

(Wherein R ¹ is —NH ₂ , —NHR ² , —OH or —SH, and R ² is a fluorine atom or a monovalent organic group)
A crosslinking agent comprising at least two crosslinkable reactive groups represented by:
(C2) Formula (2):

A cross-linking agent represented by
(C3) Formula (3):

(Wherein Rf ¹ is a C 1-10 perfluoroalkylene group)
And (C4) Formula (4):

(Where n is an integer from 1 to 10)
The method for producing a composition according to claim 1, wherein the composition is at least one kind of crosslinking agent selected from the group consisting of crosslinking agents represented by the formula: A fluorine-containing elastomer composition for crosslinking obtained by the method for producing a fluorine-containing elastomer composition for crosslinking according to any one of claims 1 to 8. A molding step (III) is included, in which the fluorine-containing elastomer composition for crosslinking is obtained by the production method according to any one of claims 1 to 8, and then the fluorine-containing elastomer composition for crosslinking is crosslinked to form a crosslinked molded product. A method for producing a fluorine-containing elastomer molded product. A fluorine-containing elastomer molded product obtained by the method for producing a fluorine-containing elastomer molded product according to claim 10. A composition comprising an organic solvent (A) and a crosslinking agent (C), wherein the crosslinking agent (C)
(C1) Formula (1):

(Wherein R ¹ is —NH ₂ , —NHR ² , —OH or —SH, and R ² is a fluorine atom or a monovalent organic group)
A crosslinking agent comprising at least two crosslinkable reactive groups represented by:
(C2) Formula (2):

A cross-linking agent represented by
(C3) Formula (3):

(Wherein Rf ¹ is a C 1-10 perfluoroalkylene group)
And (C4) Formula (4):

(Where n is an integer from 1 to 10)
The composition which is at least 1 sort (s) of crosslinking agent chosen from the group which consists of a crosslinking agent shown by these. The composition according to claim 12, further comprising a fluorine-containing elastomer. The composition according to claim 12 or 13, wherein the organic solvent (A) is at least one selected from the group consisting of ketone solvents, amide solvents, ester solvents, ether solvents, sulfolane solvents, and carbonate solvents. .