EP1525238A2 - Copolymere de fluoroelastomere a base de tetrafluoroethylene, de chlorotrifluoroethylene, d'hexafluoropropylene et de fluorure de vinylidene - Google Patents
Copolymere de fluoroelastomere a base de tetrafluoroethylene, de chlorotrifluoroethylene, d'hexafluoropropylene et de fluorure de vinylideneInfo
- Publication number
- EP1525238A2 EP1525238A2 EP03771235A EP03771235A EP1525238A2 EP 1525238 A2 EP1525238 A2 EP 1525238A2 EP 03771235 A EP03771235 A EP 03771235A EP 03771235 A EP03771235 A EP 03771235A EP 1525238 A2 EP1525238 A2 EP 1525238A2
- Authority
- EP
- European Patent Office
- Prior art keywords
- fluoropolymer
- cure
- repeating units
- composition
- fluoroelastomer
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F214/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen
- C08F214/18—Monomers containing fluorine
Definitions
- the present invention relates to fluoropolymers suitable for the preparation of a fluoroelastomer and in particular to a fluoropolymer that comprises repeating units derived from tetrafluoroethylene (TFE), hexafluoropropylene (HFP), vinylidene fluoride (VDF) and chlorotrifluoroethylene (CTFE).
- TFE tetrafluoroethylene
- HFP hexafluoropropylene
- VDF vinylidene fluoride
- CTFE chlorotrifluoroethylene
- the invention further relates to a curable fluoroelastomer composition based on a TFE/HFP/VDF/CTFE copolymer and to a fuel management system including a fluoroelastomer obtained from curing the fluoroelastomer composition.
- Fluoroelastomers are elastomers prepared by curing a fluoroelastomer precursor ("gum") made from monomers containing one or more atoms of fluorine, or copolymers of such monomers with other monomers, the fluoromonomer(s) being present in the greatest amount by mass.
- the fluoroelastomer precursor is a fluoropolymer that is suitable to prepare a fluoroelastomer having desired elasticity properties.
- the fluoroelastomer precursor is an amorphous fluoropolymer or a fluoropolymer that hardly shows a melting point.
- Fluoroelastomers have been used successfully in a number of applications due to their ability to withstand high temperatures and aggressive chemicals, as well as the ability of the fluoroelastomer gum to be processed using standard elastomer processing equipment.
- fluoroelastomers have been used in fuel management systems such as automotive fuel hoses, filler neck hoses, injector o-rings, and the like. Fuel management applications require low fuel vapor permeation in combination with good low temperature properties, sealability, and flexural properties.
- Fluoroelastomers with high fluorine content show good fuel permeation resistance.
- high-fluorine content fluoroelastomers such as high- fluorine content terpolymers based on tetrafluoroethylene, vinylidene fluoride, and hexafluoropropylene have some limitations.
- the tetrafluoroethylene content (and thus the fluorine content) is high, flexibility and processability tend to be compromised.
- the high fluorine content may render a fluoroelastomer too stiff for curative incorporation on ⁇ standard processing equipment such as roll mills or Banbury mixers, which requires a material with a melting point less than about 100° C.
- the hexafluoropropylene content at the expense of vinylidene fluoride, is too high, the polymerization rate may become unacceptably slow for commercial production.
- US 4,696,989 also discloses THV copolymers for producing fluoroelastomers.
- this patent teaches specific ratios of the composing monomers in the ternary diagram as yielding fluoroelastomers that are particularly suitable for use in wire coating where good insulating performance, moldability, heat resistance, flame retardance and flexibility are desired.
- US 4,696,989 is not specifically concerned with providing fluoroelastomers that have excellent properties for use in fuel management systems.
- THV fluoroelastomers Despite the many known fluoroelastomers, and in particular THV fluoroelastomers, there continues to be a desire to find further THV based fluoroelastomer compositions that have excellent properties for use in fuel management systems. In particular, it is a desire to find THV based fluoroelastomers that can be manufactured in a convenient and cost effective way, that have good processing properties, good flexibility and that have properties that make them particularly suitable for use in a fuel management system. Thus, it will typically be desired that the THV fluoroelastomers have low gas and fuel vapor permeation.
- the present invention provides a fluoropolymer suitable for the preparation of a fluoroelastomer.
- the fluoropolymer comprises: a. 10 to 50 mole % of repeating units derived from tetrafluoroethylene; b. 15 to 40 mole % of repeating units derived from hexafluoropropylene; c. 25 to 59 mole % of repeating units derived from vinylidene fluoride; d. 1 to 20 mole % of repeating units derived from chlorotrifluoroethylene; and optionally e. one or more repeating units derived from fluorinated monomers other than tetrafluoroethylene, hexafluoropropylene, vinylidene fluoride and chlorotrifluoroethylene.
- the total amount of repeating units a to e typically total to 100%.
- a fluoropolymer can be produced at high polymerization rates, in particular at higher rates than corresponding THV copolymers that do not include units derived from CTFE.
- a fluoropolymer can be prepared that has a high fluorine content while maintaining a high flexibility and good sealability when cured to a fluoroelastomer.
- the fluoroelastomers prepared therefrom have excellent gas and vapor permeation properties so as to make them particularly suitable for use in a fuel management system.
- any system or component of a system that may be used in the handling of fuel and includes for example fuel hoses, fuel tanks, filler neck hoses, liners and the like.
- CTFE in the copolymer improves the bonding properties of the fluoropolymer to other substrates including elastomeric layers such as silicone rubbers when bonded to these substrates in the presence of an organic compound having one or more hydride functions MH wherein M is selected from the group consisting of Si, Ge, Sn and Pb.
- This organic compound can be present in the fluoropolymer composition from which the fluoroelastomer is prepared or can be present in a layer of the substrate.
- the improved bonding properties are of particular interest in fuel management systems where it may be required to bond the fluoroelastomer to other non-fluorinated components of the fuel management system.
- the invention provides a curable fluoroelastomer composition comprising the above-defined fluoropolymer and a cure composition.
- the invention provides a fuel management system that comprises a fluoroelastomer obtained by curing a curable fluoroelastomer composition having the fluoropolymer and a cure composition.
- the fluoroelastomer of the fuel management system may comprise a coating as well as a shaped article.
- the invention provides a method of making a fluoropolymer as described above, comprising an aqueous emulsion polymerization of tetrafluoroethylene, hexafluoropropylene, vinylidene fluoride, chlorotrifluoroethylene and optional further fluorinated monomers in an amounts appropriate so as to obtain the fluoropolymer having the composition as described above.
- the fluoropolymer suitable for preparing the fluoroelastomer comprises repeating units of TFE, HFP, VDF and CTFE in the amounts recited above in the summary of the invention.
- Preferred amounts of the repeating units deriving from TFE are from 15 to 45 mole%
- preferred amounts of the repeating units deriving from HFP are from 20 to 35 mole%
- preferred amounts of repeating units deriving from VDF are from 28 to 58 mole%
- preferred amounts of repeating units deriving from CTFE are from 2 to 15 mole%.
- the fluoropolymer may comprise repeating units deriving from other fluorinated monomers.
- a particularly preferred fluorinated co-monomer for including in the fluoropolymer is a fluorinated vinyl ether and in particular a perfluorinated vinyl ether.
- the amount of repeating units deriving from the (per)fluorinated vinyl ether, when present, may be up to 25 mole %, preferably up to 18 mole %, more preferably up to 15 mole%.
- CF 2 CFO(R a O) n (R b fO) m R c f
- R a f and R b f are different linear or branched perfluoroalkylene groups of 1-6 carbon atoms, in particular 2 to 6 carbon atoms
- m and n are independently 0-10
- R c f is a perfluoroalkyl group of 1-6 carbon atoms.
- R d f represents a perfluoroalkyl group of 1 to 10, preferably 1 to 5 carbon atoms.
- a typical example of a perfluoroalkyl vinyl monomer is hexafluoropropylene.
- the fluoropolymer for preparing the fluoroelastomer may have a bi-modal or multi- modal molecular weight distribution to enhance the processing properties of the fluoropolymer. Generally, the fluoropolymer will have a weight average molecular weight between 10,000 to 500,000 g/mol.
- the fluoropolymer suitable for curing to a fluoroelastomer is typically prepared by a free radical polymerization.
- the free radical polymerization is generally initiated through the use of free radical generating initiators.
- free radical polymerization is generally initiated through the use of free radical generating initiators.
- initiators one can use any of the known initiators commonly employed in the polymerization of fluorinated olefins such as tetrafluoroethylene. For example peroxides can be used as free radical initiators.
- peroxide initiators include, hydrogen peroxide, diacylperoxides such as diacetylperoxide, dipropionylperoxide, dibutyrylperoxide, dibenzoylperoxide, benzoylacetylperoxide, diglutaric acid peroxide and dilaurylperoxide, and further water soluble per-acids and water soluble salts thereof such as e.g. ammonium, sodium or potassium salts.
- per-acids include peracetic acid. Esters of the peracid can be used as well and examples thereof include tert.- butylperoxyacetate and tert.-butylperoxypivalate.
- a further class of initiators that can be used are water soluble azo-compounds.
- Suitable redox systems for use as initiators include for example a combination of peroxodisulphate and hydrogen sulphite or disulphite, a combination of thiosulphate and peroxodisulphate, a combination of peroxodisulphate and hydrazine or azodicarboxamide (including salts thereof, preferably alkali or ammonium salts).
- Further initiators that can be used are ammonium- alkali- or earth alkali salts of permanganic or manganic acid or manganic acids.
- the amount of initiator employed is typically between 0.03 and 2 % by weight, preferably between 0.05 and 1 % by weight based on the total weight of the polymerization mixture.
- the full amount of initiator may be added at the start of the polymerization or the initiator can be added to the polymerization in a continuous way during the polymerization until a conversion of 70 to 80% is achieved.
- Preferred initiator systems include peroxodisulphate and permanganate.
- the free radical polymerization may be carried out in an organic solvent, can be a aqueous suspension polymerization or an aqueous emulsion polymerization. An aqueous emulsion polymerization is preferred in the present invention.
- the fluorinated monomers are polymerized in the aqueous phase generally in the presence of a free radical initiator and a fluorinated surfactant or emulsifier, preferably a non-telogenic emulsifier.
- the emulsifier will generally be used in amounts less than 1% by weight, for example from 0.1 to 1% by weight based on the weight of the aqueous phase.
- fluorinated emulsifiers include salts, in particular ammonium salts of linear or branched perfluoro alkyl containing carboxylic and sulphonic acids having 4 to 11 carbon atoms in the alkyl chain.
- perfluorooctanoic acid ammonium salt APFO, described in US 2,567,011
- C 8 F ⁇ 7 S0 3 Li which is ' commercially available from Bayer AG
- C 4 F 9 S0 3 Li and C 4 F 9 S0 3 K
- a further example of a perfluoroalkyl containing carboxylic acid salt is C 8 F ⁇ 7 S0 2 N(C 2 H 5 )CH 2 COOK (described in US 2,809,990).
- Still further emulsifiers that can be used include perfluoropolyethercarboxylate emulsifiers such as disclosed in EP 219065.
- APFO is the preferred emulsifier as it can be more readily removed from the polymerization product at the end of polymerization.
- the aqueous emulsion polymerization may also be carried out without addition of a fluorinated emulsifier.
- Such a polymerization is for example described in WO 96/24622 and WO 97/17381.
- an aerosol of a liquid fluorinated monomer or a liquid fluorinated, preferably perfluorinated, hydrocarbon compound is provided, steam heated and fed into the polymerization vessel.
- the advantage of this embodiment is that the incorporation of CTFE into the fluoropolymer is improved, which is particularly desirable when no fluorinated emulsifier or surfactant is added in the polymerization system. It will be appreciated by one skilled in the art that this finding is not particularly limited to the nature of the fluoropolymer and therefore can also be used to improve incorporation of CTFE in other fluoropolymers than those that are subject of this invention.
- liquid By the term 'liquid' is meant that the respective components are liquid at ambient temperature (20°C) and pressure (1 atm).
- suitable liquid fluorinated monomers for use with this embodiment are liquid (per)fluorinated vinyl ethers, for example of the formula set forth above.
- Suitable fluorinated hydrocarbons include those having from 3 to 25 carbon atoms and include highly fluorinated hydrocarbons containing not more than 1 or 2 hydrogen atoms as well as perfluorinated hydrocarbons.
- perfluorinated hydrocarbons include perfluorinated saturated linear, branched and/or cyclic aliphatic compounds such as a perfluorinated linear, branched or cyclic alkane; a perfluorinated aromatic compound such as perfluorinated benzene, or perfluorinated tetradecahydro phenanthene. It can also be a perfluorinated alkyl amine such as a perfluorinated trialkyl amine.
- It can further be a perfluorinated cyclic aliphatic, such as decalin; and preferably a heterocyclic aliphatic compound containing oxygen or sulfur in the ring, such as perfluoro-2-butyl tetrahydrofuran.
- a perfluorinated cyclic aliphatic such as decalin
- a heterocyclic aliphatic compound containing oxygen or sulfur in the ring such as perfluoro-2-butyl tetrahydrofuran.
- perfluorinated hydrocarbons include perfluoro-2- butyltetrahydrofuran, perfluorodecalin, perfluoromethyldecalin, perfluoromethylcyclohexane, perfluoro(l,3-dimethylcyclohexane), perfluorodimethyldecahydronaphthalene, perfluorofluoorene, perfluoro(tetradecahydrophenanthrene), perfluorotetracosane, perfluorokerosenes, octafluoronaphthalene, oligomers of poly(chlorotrifluoroethylene), perfluoro(trialkylamine) such as perfluoro(tripropylamine), perfluoro(tributylamine), or perfluoro(tripentylamine), and octafluorotoluene, hexafluorobenzene, and commercial fluorinated solvents, such as Fluorinert FC-
- the aqueous emulsion polymerization can be carried out continuously in which, for example, monomers, water, optionally further emulsifiers, buffers and catalysts are fed continuously to a stirred reactor under optimum pressure and temperature conditions while the resulting emulsion or suspension is removed continuously.
- An alternative technique is batch or semibatch (semi-continuous) polymerization by feeding the ingredients into a stirred reactor and allowing them to react at a set temperature for a specified length of time or by charging ingredients into the reactor and feeding the monomers into the reactor to maintain a constant pressure until a desired amount of polymer is formed.
- the polymerization can be carried out in a standard or conventional vessel used for emulsion polymerization of gaseous fluorinated monomers.
- the polymerization systems may comprise auxiliaries, such as buffers and, if desired, complex-formers or chain-transfer agents including for example alkanes such ethane and n- pentane, dialkyl ethers such as dimethyl ether, methyl tertiary butyl ether and chlorine or bromine containing chain transfer agents.
- the polymerization temperature may be from 10 to 180°C, typically 30°C to 100°C.
- Polymerization pressures may be from 1 to 40 bar, typically 3 to 30 bar.
- the fluoropolymer may be prepared by initiating the free radical polymerization in the presence of a chloride salt.
- a chloride salt As a result of the presence of the chloride salt, the number of polar and in particular ionic end groups can be reduced and CF 2 C1 end groups are formed. This was found to enhance the processing characteristics of the fluoropolymer. Further, the CF 2 C1 end groups may also further improve the bonding properties of the bonding properties of the fluoroelastomer to other substrates, particularly when an organic compound having MH functions as mentioned above is present.
- a curable fluoroelastomer composition according to the invention comprises the fluoropolymer and a cure composition.
- a curable fluoroelastomer composition may be cured by any of the methods known to those skilled in the art.
- the cure composition typically includes one or more components that cause the fluoropolymer chains to link with each other thereby forming a three dimensional network.
- Such components may include catalysts, curing agents and/or coagents.
- a so called peroxide cure system may be used.
- the fluoropolymer is provided with one or more cure sites that comprise a halogen capable of participating in a peroxide cure reaction and the composition for providing the fluoropolymer contains an organic peroxide.
- the halogen capable of participating in a peroxide cure reaction is typically bromine or iodine and may be distributed along the polymer chain and/or may be contained in the end groups of the fluoropolymer.
- the amount of bromine or iodine contained in the fluoropolymer is between 0.001 and
- the fluoropolymers of this invention which contain chlorine atoms by virtue of units deriving from CTFE can be used for curing in a peroxide cure reaction.
- the fluoropolymer may additionally be modified with bromine and/or iodine.
- the copolymerization of the basic monomers of the fluoropolymer may be carried out with a suitable fluorinated cure-site monomer (see for instance U.S. Pat. Nos. 4,745,165, 4,831,085, and 4,214,060).
- a suitable fluorinated cure-site monomer see for instance U.S. Pat. Nos. 4,745,165, 4,831,085, and 4,214,060.
- Such comonomer can be selected for instance from:
- Z'-R' r CF CF 2 Z'-RV-
- the fluoropolymer can contain a cure site component in terminal position, deriving from a suitable chain transfer agent introduced in the reaction medium during the polymer preparation, as described in U.S. Pat. No. 4,501,869 or derived from a suitable initiator.
- the chlorine of the CF 2 C1 end groups introduced when chloride salt is present in the initiation of the free radical polymerization, can also participate in a peroxide cure reaction.
- chain transfer agents examples include those having the formula R Br x , wherein R f is a x-valent (per)fluoroalkyl radical -C ⁇ , optionally containing chlorine atoms, while x is 1 or 2. Examples include CF 2 Br 2 , Br(CF 2 ) 2 Br, Br(CF 2 ) 4 Br, CF 2 ClBr, CF 3 CFBrCF 2 Br and the like. Further examples of suitable chain transfer agents include CH 2 Br 2 , CH 2 I 2 and those disclosed in
- Suitable organic peroxides are those which generate free radicals at curing temperatures.
- a dialkyl peroxide or a bis(dialkyl peroxide) which decomposes at a temperature above 50° C is especially preferred.
- a di-tertiarybutyl peroxide having a tertiary carbon atom attached to peroxy oxygen is particularly preferred.
- the most useful peroxides of this type are 2,5-dimethyl-2,5-di(tertiarybutylperoxy)hexyne-3 and 2,5-dimethyl-2,5- di(tertiarybutylperoxy)hexane.
- peroxides can be selected from such compounds as dicumyl peroxide, dibenzoyl peroxide, tertiarybutyl perbenzoate, , '-bis(t-butylperoxy- diisopropylbenzene), and di[l,3-dimethyl-3-(t-butylperoxy)-butyl]carbonate. Generally, about 1-3 parts of peroxide per 100 parts of fluoropolymer is used.
- the cure site component may also comprise a nitrile group-containing cure site monomer.
- CF 2 CFO[CF 2 CF(CF 3 )0] g (CF 2 ) v OCF(CF 3 )CN
- CF 2 CF[OCF 2 CF(CF 3 )] k O(CF 2 ) u CN
- R f is a perfluoroalkylene or a bivalent perfluoroether group.
- a catalyst comprising one or more ammonia-generating compounds may be used to cause curing.
- Ammonia-generating compounds include compounds that are solid or liquid at ambient conditions but that generate ammonia under conditions of cure. Such compounds include, for example, hexamethylene tetramine (urotropin), dicyan diamid, and metal-containing compounds of the formula:
- a W+ (NH 3 ) V Y W" where A w+ is a metal cation such as Cu 2+ , Co 2+ , Co 3+ , Cu + , and Ni 2+ ; w is equal to the valance of the metal cation; Y w" is a counterion, typically a halide, sulfate, nitrate, acetate or the like; and v is an integer from 1 to about 7.
- ammonia-generating compounds are substituted and unsubstituted triazine derivatives such as those of the formula:
- R is a hydrogen or a substituted or unsubstituted alkyl, aryl, or aralkyl group having from 1 to about 20 carbon atoms.
- Specific useful triazine derivatives include hexahydro- 1,3,5 -s- triazine and acetaldehyde ammonia trimer.
- the fluoropolymers including a nitrile containing cure site component can also be cured using one or more peroxide curatives along with the ammonia generating catalysts. Suitable peroxide curatives for this purpose include those listed above. It will further be understood by one skilled in the art that the curable fluoroelastomer composition may include a mixture of cure site components, such as a mixture of nitrile containing cure sites and cure sites including a halogen capable of participating in a peroxide cure reaction. In the latter case, a mixture of ammonia generating compounds and peroxides will generally be employed. To cure the nitrile containing fluoropolymers all other well-known compounds can be used, like amino phenols (U.S. 5,677,389), ammonia salts (U.S. 5,565,512), amidoxines (U.S. 5,668,221) and other ammonia generating comp (PCT 00/09603) or imidates.
- PCT 00/09603
- These coagents can be added in an amount equal to 0.1 and 10 parts per hundred parts fluoropolymer, preferably between 2-5 parts per hundred parts fluoropolymer.
- useful coagents include triallyl cyanurate; triallyl isocyanurate; triallyl trimellitate; tri(methylallyl) isocyanurate; tris(diallylamine)-s-triazine; triallyl phosphite; N,N-diallyl acrylamide; hexaallyl phosphoramide; N,N,N',N'-tetraaIkyl tetraphthalamide; N,N,N',N'- tetraallyl malonamide; trivinyl isocyanurate; 2,4,6-trivinyl methyltrisiloxane; N,N'-m- phenylenebismaleimide; diallyl-phthalate and tri(5-norbornene-2-methylene)cyanurate. Particularly useful is triallyl isocyanurate.
- Other useful coagents include the bis-olefms disclosed in EPA 0 661 304 Al, EPA 0 784 064 Al and
- curing of the fluoropolymer may be effected using a polyhydroxy compound and the cure composition will thus comprise a polyhydroxy compound.
- the advantage of using a polyhydroxy compound for curing the fluoropolymer is that it will not be necessary to include special cure site components in the fluoropolymer.
- a polyhydroxy curing system generally also comprises one or more organo-onium accelerators in addition to the polyhydroxy compound.
- the organo-onium compounds useful in the present invention typically contain at least one heteroatom, i.e., a non- carbon atom such as N, P, S, O, bonded to organic or inorganic moieties and include for example ammonium salts, phosphonium salts and iminium salts.
- One class of quaternary organo-onium compounds useful in the present invention broadly comprises relatively positive and relatively negative ions wherein a phosphorus, arsenic, antimony or nitrogen generally comprises the central atom of the positive ion, and the negative ion may be an organic or inorganic anion (e.g., halide, sulfate, acetate, phosphate, phosphonate, hydroxide, alkoxide, phenoxide, bisphenoxide, etc.).
- organic or inorganic anion e.g., halide, sulfate, acetate, phosphate, phosphonate, hydroxide, alkoxide, phenoxide, bisphenoxide, etc.
- Another class of useful organo-onium compounds include those having one or more pendent fluorinated alkyl groups. Generally, the most useful fluorinated onium compounds are disclosed by Coggio et al. in U.S. Pat. No. 5,591,804.
- the polyhydroxy compound may be used in its free or non-salt form or as the anionic portion of a chosen organo-onium accelerator.
- the crosslinking agent may be any of those polyhydroxy compounds known in the art to function as a crosslinking agent or co-curative for fluoropolymers, such as those polyhydroxy compounds disclosed in U.S. Pat. Nos. 3,876,654 (Pattison), and 4,233,421 (Worm).
- One of the most useful and commonly employed aromatic polyphenols is 4,4'-hexafluoroisopropylidenyl bisphenol, known more commonly as bisphenol AF.
- the compounds 4,4'-dihydroxydiphenyl sulfone (also known as Bisphenol S) and 4,4'- isopropylidenyl bisphenol (also known as bisphenol A) are also widely used in practice.
- the cure composition based on polyhydroxy compounds may further include an acid acceptor.
- Acid acceptors can be inorganic or blends of inorganic and organic. Examples of inorganic acceptors include magnesium oxide, lead oxide, calcium oxide, calcium hydroxide, dibasic lead phosphite, zinc oxide, barium carbonate, strontium hydroxide, calcium carbonate, etc.
- Organic acceptors include epoxies, sodium stearate, and magnesium oxalate.
- the preferred acid acceptors are magnesium oxide and calcium hydroxide.
- the acid acceptors can be used singly or in combination, and preferably are used in amounts ranging from about 2 to 25 parts per 100 parts by weight of the fluoropolymer.
- the cure composition may comprise an organic peroxide and a polyhydroxy based cure system as described above.
- Such cure composition can be used with a fluoropolymer that has a halogen capable of participating in a peroxide cure reaction as well as with fluoropolymers that do not contain such halogens. If the fluoropolymer has halogens capable of participating in the peroxide cure reaction, a cure composition having a polyhydroxy compound and a peroxide can provide for a so called dual cure.
- an organic peroxide in the cure composition is particularly beneficial if the fluoropolymer is to form a fluoroelastomer layer bonded to another elastomer that is also formed with the use of a peroxide cure system such as for example in case of a silicone based elastomer.
- the curable fluoroelastomer composition may contain further additives, such as carbon black, stabilizers, plasticizers, lubricants, fillers, and processing aids typically utilized in fluoropolymer compounding can be incorporated into the compositions of the present invention, provided they have adequate stability for the intended service conditions.
- the curable fluoroelastomer compositions may be prepared by mixing the fluoropolymer, the cure composition and optionally the organic compound having hydride function(s) and other additives in conventional rubber processing equipment. Such equipment includes rubber mills, internal mixers, such as Banbury mixers, and mixing extruders.
- the fluoropolymer has improved bonding properties to other substrates, particularly in the presence of an organic compound having hydride functions MH.
- a peroxide curable fluoropolymer composition can be obtained.
- the organic compound include siloxanes or silazenes that comprise one or more MH functions.
- the MH functions will be -SiH functions.
- the SiH function will be an -OSiH or a -NSiH whereby the hydrogen is attached to a silicon atom that is further bonded to an oxygen or nitrogen atom.
- the siloxane or silazene may be a simple low molecular weight organic compound or may be a polymeric compound including for example a polysiloxane which may be linear, branched or cyclic. Specific examples include HSi(OCH 2 CH 3 ) 3 , (CH 3 ) 2 (CH 3 CH 2 O)SiH, 1,1,3,3 tetraisopropyl disiloxane, diphenyl-1,1,3,3- tetrakis(dimethylsiloxy)disiloxane available from United Chem, silylhydride terminated poly(dimethylsiloxane), poly(methyl hydro siloxane) and copolymers of dimethylsiloxane and methylhydrosiloxane, 1,3,5-trimethyl cyclosiloxane and l-phenyl-3,3,5,5-tetramethyl cyclosiloxane.
- Polysiloxanes and siloxanes having SiH groups are known in the art and can be produced according to well-known procedures such as disclosed in for example: Encyclopedia of Polymer Science and Engineering, Second Edition, VI 5, Silicones, pgs. 204-308, John Wiley
- Siloxanes having SiH groups are also generally commercially available.
- the siloxane or polysiloxane will have a molecular weight between 150g/mol and 10 OOOg/mol.
- the organic compound may also be a compound that corresponds to the formula:
- R represents a hydrocarbon group optionally comprising one or more substituents and wherein the R groups may be the same or different and whereby two R groups may be linked to each other so as to form a ring
- M is selected from Si, Ge, Sn and Pb
- q is a value of 1 to 3
- x is a value of 1 to 3
- substituents that may be present on the hydrocarbon group R include alkoxy, aryloxy, halogens such as chlorine and bromine, nitrile groups, hydroxy groups and amino groups.
- the backbone of the hydrocarbon group may further be interrupted by one or more heteroatoms such as for example oxygen and nitrogen atoms.
- Typical examples of hydrocarbon groups include saturated or unsaturated linear, branched or cyclic aliphatic groups and aromatic groups. Specific examples are C 1 -C 5 alkyl groups, aryl groups having 6 to 12 carbon atoms, arylalkyl and alkylaryl groups having 7 to 14 carbon atoms.
- Compounds of formula (I) above are known and have been described in for example J. Am. Chem. Soc, 116 (1994), page 4521-4522.
- Examples include tri(n-butyl)tin hydride, tri(ethyl)silyl hydride, di(trimethylsilyl)silylmethyl hydride, tri(trimethylsilyl)silyl hydride, tri(phenyl)silyl hydride.
- Compounds of formula (I) have further been disclosed in EP 761 735.
- melt flow index was carried out according to DIN 53735, ISO 12086 or ASTM D- 1238 at a support weight of 5.0 kg and a temperature of 265°C or 297°C alternatively.
- the MFI was obtained with a standardized extrusion die of 2.1 mm diameter and a length of 8.0 mm.
- a strain controlled ARES rheometer of Rheometry Scientific was used to evaluate the processability of the fluoropolymer in frequency sweep experiments.
- the viscosity data were determined at various shear rates at 265°C in nitrogen atmosphere using a 25 mm parallel plate geometry and typically 10% strain.
- SEC Size Exclusion Chromatography
- the latex particle size determination was conducted by means of dynamic light scattering with aMalvern Zetazi ⁇ er 1000 HSA in accordance to ISO/DIS 13321. The reported average particle size is the Z-average.
- the polymer latexes as yielded from the polymerizations were diluted with 0.001 mol/L KCl-solution, the measurement temperature was 20°C in all cases.
- the vapor transmission (permeation rate) in accordance to ASTM
- test fluid a mixture of 42.5% toluene, 42.5% isooctane and 15% methanol by volume was used as test fluid.
- Sheets of 0.75-0.90 mm thickness of each polymer composition were press-cured. 3 inch diameter samples were die cut from each sheet.
- the cups were assembled by placing 100 ml of fluid in the cup, a 0.5 mm gasket between the cup and the sample, and a 1.5 mm gasket between the sample and the clamping ring. Because the samples were extensible during testing, a 16-mesh circular screen was placed between the upper gasket and the clamping ring. All tests were conducted at 40°C for 32 days with the cup maintained in the upright position. The first 7 days of testing, no data were collected in order to allow the sample to reach vapor transmission equilibrium. Then the cups were weighted approximately every other day. The transmission rate was then multiplied by the thickness of the samples in millimeters to normalize each value.
- a polymerization vessel with a total volume of 186.1 1 equipped with an impeller agitator system was charged with 114.6 1 deionized water 950 g of a 30 weight % aqueous solution of perfluorooctanoate ammonium salt (FX 1006 of 3M Company, APFO).
- FX 1006 perfluorooctanoate ammonium salt
- the vessel was degassed and subsequently charged with nitrogen to assure that all oxygen had been removed.
- the vessel was then heated up to 71°C and the agitation system was set to 210 rpm.
- the vessel was charged with ethane to a pressure of 0.6 bar absolute, with HFP to 13.4 bar absolute, with VDF to 14.1 bar absolute and with TFE to 15.5 bar absolute reaction pressure.
- the polymerization was initiated by 983 g 30% APS solution (ammonium peroxodisulfate).
- the reaction pressure of 15.5 bar absolute was maintained by the feeding TFE, HFP and VDF into the gas phase with a feeding ratio HFP (kg)/TFE (kg) of 1.011 and VDF (kg)/TFE (kg) of 0.528.
- the reaction temperature of 71°C was also maintained.
- the feeding of 22 kg TFE was completed and the monomer valves were closed.
- the reactor was vented and flushed with N 2 in three cycles.
- the so obtained 171 kg polymer dispersion had a solid content of 32%.
- the latex particle diameter was 141 nm as measured by dynamic light scattering.
- the composition of the resulting fluoropolymer was 40 mol% TFE, 27% mol% HFP, 33 mol% VDF.
- the fluorine content of the fluoropolymer was 72.5 wt%.
- a polymer according to the invention was prepared under the similar conditions as for the comparative fluoropolymer of Example 1.
- the reaction vessel of Example 1 was pressured up with ethane to a pressure of 0.8 bar absolute, with CTFE to 1.2 bar absolute, with HFP to 11.2 bar absolute, with VDF to 13.1 bar absolute and with TFE to 15.5 bar absolute reaction pressure.
- the polymerization was initiated by 983 g 30%) APS solution.
- the fluoropolymer had the following composition 7.2 mol% CTFE, 22.6 mol% HFP, 30.2mol % VDF and 40 mole% TFE.
- the fluorine content was 72.4 wt% and the total halogen content was 73.1 wt%>.
- the polymer workup was conducted analogous to Example 1, the polymer showed a very slight melting transition at 49°C and a heat of fusion of 0.3 J/g.
- the polymer had a MFI(265/5) of 189 g/10'.
- a fluoropolymer according to the invention was prepared in the same reaction vessel and under the similar conditions as for Example 1 & 2 with the exception that no APFOA was used.
- the vessel was charged with 235 g of PPVE-2 (fed as steam heated aerosol) to a pressure of 0.62 bar absolute, with 204 g CTFE to 1.17 bar absolute, with 4760 g HFP to 10.87 bar absolute, with 456 g VDF to 12.97 bar absolute and with 890 g TFE to 15.50 bar absolute reaction pressure.
- the polymerization was initiated by the addition of 980 g 30% aqueous ammonium- peroxodisulfate (APS) solution.
- APS ammonium- peroxodisulfate
- the reaction pressure of 15.5 bar absolute is maintained by the feeding TFE, HFP, CTFE and VDF into the gas phase with a feeding ratio CTFE (kg)/TFE (kg) of 0.209, HFP (kg)/TFE (kg) of 0.846 and VDF (kgVTFE (kg) of 0.482.
- CTFE 0.209
- HFP 0.846
- VDF 0.846
- VDF 0.846
- VDF 0.846
- VDF kgVTFE (kg) of 0.482.
- PPVE-2 is additionally fed as heated aerosol with a feeding a feeding rate 50 g/h.
- the reaction temperature of 71 °C is also maintained.
- a liquid dispersion sample was taken from the reactor and 85 g of ethane chain transfer agent is charged into the vessel which results in a substantial decrease of the polymerization rate.
- the polymerization is continued until the feeding of 21.0 kg TFE is completed after 4 h and 35 min total polymerization time. After the monomer valves are closed, the monomer gas phase is reacted down to a vessel pressure of 11.6 bar within 15 min. The reactor is vented and flushed with N 2 in three cycles.
- the so obtained 168 kg polymer dispersion had a solid content of 31%, the following polymer workup was conducted analogous to Example 1.
- the fluoropolymer had the following composition: 7.2 mol% CTFE, 39.9 mol%TFE, 30.2 mol% VDF, 22.6 mol% HFP and 0.1 mol%
- the fluorine content was 72.2 wt% and the total halogen content was 73.1 wt%.
- the polymer shows a slight melting transition at 88°C and a heat of fusion of 0.8 J/g.
- the polymer has a MFI(265/5) of 188 g/10'.
- the dispersion sample that was taken at 10.5 kg TFE feed was worked up under equivalent conditions, this sample had a MFI of 18.8 g/10'.
- the polymers of Example 1 to 3 were press-cured using a bisphenol cure composition and various physical properties were measured.
- 100 parts of the polymer were mixed on a two roll mill with the following ingredients: (mmhr below means milimole per hundred parts by weight of the fluoropolymer) • 5.94 (mmhr) Bisphenol AF • 0.54 (mmhr) of the following phosphonium complex (C 4 H 9 ) 3 P + CH 2 CH(CH 3 )OCH 3 OC 6 H 4 C(CF 3 ) 2 C 6 H 4 OH which is tributylmethoxy propyl phosphonium chloride prepared from tributyl phosphene (available from Cytec) allylchloride and methanol and then reacting with the sodium salt of Bisphenol AF.
- a further complex which is a complex prepared by reacting tributylmethoxy propyl phosphonium chloride with the sodium salt of perfluoroctyl-n-methylsulfonamide.
- the following other compounding ingredients were also added: 3 g per hundred gram (phr) fluoropolymer magnesium oxide (Elastomag 170 from Morton International) and 6 phr calcium hydroxide and 20 phr carbon black (N762).
- the composition was prepared in the form of individual sheets measuring 76 x 152 x 2 mm by pressing at 5-7 MPa at 165°C for 50 min. Finally, all three cured compounds were tested and compared for various properties according to the test protocols set forth above. The test results are reported in Table 2.
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Abstract
La présente invention concerne un fluoropolymère approprié pour la préparation d'un fluoroélastomère. Ledit fluoropolymère comprend généralement des motifs répétés dérivés des monomères tétrafluoroéthylène, hexafluoropropylène, fluorure de vinylidène, chlorotrifluoroéthylène et éventuellement un ou plusieurs motifs répétés de monomères fluorés autres que tétrafluoroéthylène, hexafluoropropylène, fluorure de vinylidène et chlorotrifluoroéthylène.
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
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US39923002P | 2002-07-29 | 2002-07-29 | |
US399230P | 2002-07-29 | ||
PCT/IB2003/005083 WO2004011543A2 (fr) | 2002-07-29 | 2003-07-25 | Copolymere de fluoroelastomere a base de tetrafluoroethylene, de chlorotrifluoroethylene, d'hexafluoropropylene et de fluorure de vinylidene |
Publications (1)
Publication Number | Publication Date |
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EP1525238A2 true EP1525238A2 (fr) | 2005-04-27 |
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Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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EP03771235A Withdrawn EP1525238A2 (fr) | 2002-07-29 | 2003-07-25 | Copolymere de fluoroelastomere a base de tetrafluoroethylene, de chlorotrifluoroethylene, d'hexafluoropropylene et de fluorure de vinylidene |
Country Status (6)
Country | Link |
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EP (1) | EP1525238A2 (fr) |
CN (1) | CN100341907C (fr) |
AU (1) | AU2003280043A1 (fr) |
RU (1) | RU2005101614A (fr) |
WO (1) | WO2004011543A2 (fr) |
ZA (1) | ZA200501646B (fr) |
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JP5532532B2 (ja) * | 2007-06-25 | 2014-06-25 | ダイキン工業株式会社 | 低分子量ポリテトラフルオロエチレン水性分散液及びその製造方法 |
JP5549668B2 (ja) * | 2008-06-30 | 2014-07-16 | ダイキン工業株式会社 | 硬化性組成物およびそれからなる成形品 |
GB0814955D0 (en) | 2008-08-18 | 2008-09-24 | 3M Innovative Properties Co | Azide-containing fluoropolymers and their preparation |
CN102161724B (zh) * | 2011-02-21 | 2013-01-16 | 山东东岳高分子材料有限公司 | 一种高透明度五元共聚含氟树脂及其制备方法与应用 |
US9830797B2 (en) | 2012-12-28 | 2017-11-28 | Eaton Corporation | High pressure hose with polymeric tube |
CN104981341B (zh) | 2012-12-28 | 2021-09-14 | 旭硝子化学美国有限公司 | 用于软管组装件的层状管道 |
CN105658429B (zh) * | 2013-05-10 | 2018-06-12 | Agc 化工美洲公司 | 层状管和用于其中的层 |
EP3183299B1 (fr) * | 2014-08-22 | 2020-11-25 | 3M Innovative Properties Company | Compositions de polymère fluorothermoplastique |
CN104530291B (zh) * | 2014-12-17 | 2016-08-24 | 中昊晨光化工研究院有限公司 | 三氟氯乙烯改性聚全氟乙丙烯树脂及其制备方法 |
CN106188377B (zh) * | 2015-05-08 | 2018-12-07 | 浙江省化工研究院有限公司 | 一种改性的含氟弹性体、其制备方法及应用 |
US10807342B2 (en) | 2015-12-15 | 2020-10-20 | Agc Chemicals Americas, Inc. | Layered tube and layer for use in same |
WO2019126298A1 (fr) * | 2017-12-22 | 2019-06-27 | 3M Innovative Properties Company | Élastomères halogénés durcis à l'aide de peroxyde possédant une couche superficielle contenant du silicium |
WO2019133410A1 (fr) * | 2017-12-28 | 2019-07-04 | 3M Innovative Properties Company | Compositions de fluoropolymères contenant des composés de silane fluorés fonctionnels |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
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DK310484A (da) * | 1983-06-30 | 1984-12-31 | Montedison Spa | Elastomerpraeparat baseret paa vinylidenfluorid |
IT1277445B1 (it) * | 1995-08-04 | 1997-11-10 | Ausimont Spa | Composizioni vulcanizzabili di fluoroelastomeri contenenti bromo |
US5955556A (en) * | 1995-11-06 | 1999-09-21 | Alliedsignal Inc. | Method of manufacturing fluoropolymers |
JP3069288B2 (ja) * | 1996-03-29 | 2000-07-24 | ニチアス株式会社 | フッ素系樹脂組成物、その製造法および成形品 |
JP3758323B2 (ja) * | 1997-07-18 | 2006-03-22 | ユニマテック株式会社 | 含フッ素エラストマーの製造法 |
ATE366777T1 (de) * | 2000-12-01 | 2007-08-15 | 3M Innovative Properties Co | Zusammensetzung zur herstellung eines fluorelastomers |
-
2003
- 2003-07-25 CN CNB03817524XA patent/CN100341907C/zh not_active Expired - Fee Related
- 2003-07-25 RU RU2005101614/04A patent/RU2005101614A/ru not_active Application Discontinuation
- 2003-07-25 WO PCT/IB2003/005083 patent/WO2004011543A2/fr active Application Filing
- 2003-07-25 AU AU2003280043A patent/AU2003280043A1/en not_active Abandoned
- 2003-07-25 EP EP03771235A patent/EP1525238A2/fr not_active Withdrawn
-
2005
- 2005-02-24 ZA ZA200501646A patent/ZA200501646B/xx unknown
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See references of WO2004011543A3 * |
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Publication number | Publication date |
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AU2003280043A8 (en) | 2004-02-16 |
RU2005101614A (ru) | 2006-01-20 |
AU2003280043A1 (en) | 2004-02-16 |
CN100341907C (zh) | 2007-10-10 |
ZA200501646B (en) | 2005-09-06 |
WO2004011543A3 (fr) | 2004-04-22 |
WO2004011543A2 (fr) | 2004-02-05 |
CN1692132A (zh) | 2005-11-02 |
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