Abstract: Fluorine-containing elastomers produced through copolymerization reaction of vinylidene fluoride, tetrafluoroethylene, perfluoro(lower alkyl vinyl ether) and chlorotrifluoroethylene in the presence of a bromine-containing monomer compound and an iodine- and bromine-containing compound, where hexafluoropropene can be further copolymerized, have not only a distinguished resistance to amine-based additives and also distinguished low-temperature characteristic and engine oil resistance, and also a lower cost attained by reduced copolymer proportion of perfluoro(lower alkyl vinyl ether).

Abstract: A bisphenol compound represented by the following general formula: ##STR1## where R is an alkylene group having 1 to 5 carbon atoms, an alkylidene group having 1 to 5 carbon atoms, a perfluoroalkylene group having 1 to 5 carbon atoms, a perfluoroalkylidene group having 1 to 5 carbon atoms, a SO.sub.2 group or an O group; and R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are the same or different alkyl groups, alkenyl groups, aryl groups, alkylaryl groups or aralkyl groups, each having 1 to 25 carbon atoms, can give vulcanization products having a good resistance to hot water, when used as a cross-linking agent for terpolymers of tetrafluoroethylene/perfluoro (alkyl vinyl ether)/ethylenically unsaturated cure site monomer.

Abstract: 2.2'-bis(3-mercaptophenyl)hexafluoropropane [bisthio-phenol AF] is obtained in good yield by chlorosulfonating 2.2'-bisphenylhexafluoropropane and reducing the thus quantitatively obtained 2,2'-bis(3-chlorosulfonylphenyl)-hexafluoropropane with zinc under acidic conditions and is effectively used as a cross-linking agent for a fluorine-containing elastomer having halogenophenyl groups as cross-linkable groups.

Abstract: A fluoroelastomer comprising 74 to 80% by mole of vinylidene fluoride, 4 to 12% by mole of tetrafluoroethylene, 14 to 18% by mole of hexafluoropropene and 0.3 to 1.3% by mole of perfluoro(alkyl vinyl ether), the sum total being 100% by mole, gives vulcanization products having well balanced high levels of low-temperature characteristics and methanol resistance, and suppressed change in the hardness with time after the secondary vulcanization.

Abstract: An adhesive composition comprising a fluorinated elastomer having dicyclopropane rings formed by reaction of chloroform with unsaturated bonds introduced into the molecule of fluorinated elastomer by an alkali treatment, as an adhesive component has a good room temperature adhesiveness and very distinguished electric characteristics perse such as a high insulation resistance, a low dielectric constant, a low dielectric loss tangent, etc. and is effectively applied to adhesion of electronic materials in printed substrates, etc.

Abstract: A vulcanization promoter for fluorine-containing elastomers prepared by (1) allowing 1.01 to 1.15 moles of a quaternary phosphonium salt to react with one mole of monoalkali metal salt of bisphenol AF in alcohol, (2) allowing 2.02 to 2.30 moles of a quaternary phosphonium salt to react with one mole of a dialkali metal salt of bisphenol AF in alcohol, (3) allowing one mole each of an alkali metal alkoxide and bisphenol AF to react with 1.01 to 1.15 moles of a quaternary phosphonium salt in alcohol or (4) subjecting one mole of bisphenol AF, 1.01 to 1.15 moles of a quaternary phosphonium salt and one mole of an alkali metal alkoxide to reaction in alcohol, each followed by further addition of the bisphenol AF thereto, or (5) allowing 1.01 to 1.15 moles of a quaternary phosphonium salt to react with one of 1/4alkali metal salt of bisphenol AF in alcohol gives much more improved vulcanization characteristics such as vulcanization speed, etc.

Abstract: A fluoroelastomer comprising 2 to 8% by mole of tetrafluoroethylene, 14 to 25% by mole of perfluoro(alkyl vinyl ether) and 70 to 85% by mole of vinylidene fluoride, sum total being 100% by mole, obtained by copolymerization in the presence of a bromine-containing monomer compound and an iodine and bromine-containing compound, has distinguished low temperature characteristics, solvent resistance and chemical resistance by itself.

Abstract: Perfluoroalkyleneethertriazine oligomer obtained by reacting a dinitrile compound NC-Rf.sup.0 --CN, where Rf.sup.0 is --(CFXOCF.sub.2).sub.a (CF.sub.2).sub.b (CF.sub.2 OCFX).sub.c --, where X is a fluorine atom or a CF.sub.3 group, a is an integer of 1 to 5, b is an integer of 1 to 2 and c is an integer of 1 to 5, or Rf.sup.0 is --CF.sub.2 O(CF.sub.2 O).sub.d CF.sub.2 --, where d is an integer of 1 to 8 with ammonia, further reacting the resulting diamizine compound with a dinitrile compound NC-Rf.sup.1 --CN, where Rf.sup.1 has the same meaning as that for Rf.sup.0 or Rf.sup.1 is a perfluoroalkylene group having 4 to 8 carbon atoms thereby obtaining a perfluoroalkyleneetherpolyimidoylamizine oligomer, then reacting the resulting oligomer with a perfluoronitrile compound Rf.sup.2 CN, where Rf.sup.2 is CF.sub.3 (OCF.sub.2).sub.e --, where e is an integer of 3 to 10, and then subjecting the resulting terminal-treated oligomer to a ring-closing reaction with a perfluoroacylating agent Rf.sup.3 COY, where Rf.sup.

Abstract: A novel fluorine-containing copolymer elastomer having bromine groups as cross-linkable groups, which comprises about 45 to about 80% by mole of tetrafluoroethylene, about 50 to about 20% by mole of a perfluoro(vinylether) represented by the following general formula:CF.sub.2 .dbd.CFO(CF.sub.2).sub.2 (OCF.sub.2)nOCF.sub.3where n is an integer of 1 to 5, and about 0.2 to about 5% by mole of a bromine-containing unsaturated monomer compound, sum total being 100% by mole, gives vulcanization products having distinguished resistances to chemicals, low temperature and heat.

Abstract: A novel fluorine-containing copolymer elastomer having bromine groups as cross-linkable groups, which comprises about 45 to about 80% by mole of tetrafluoroethylene, about 50 to about 20% by mole of a perfluoro(vinylether) represented by following general formula:CF.sub.2 .dbd.CFO(CF.sub.2).sub.2 (OCF.sub.2)nOCF.sub.3where n is an integer of 1 to 5, and about 0.2 to about 5% by mole of a bromine-containing unsaturated monomer compound, sum total being 100% by mole, gives vulcanization products having distinguished resistances to chemicals, low temperature and heat.

Abstract: A peroxide-vulcanizable fluorine-containing elastomer containing iodines as cross-linking sites, capable of producing vulcanization products having a distinguished heat resistance is produced by polymerization reaction of a fluorinated olefin having 2 to 8 carbon atoms in the presence of a diiodide compound represented by the following general formula:I--R--where R is a divalent fluorohydrocarbon group, chlorofluorohydrocarbon group or hydrocarbon group, having 2 to 8 carbon atoms, respectively, and 2,2-difluoroiodoethylene.

Abstract: A novel fluorine-containing copolymer elastomer having bromine groups as cross-linkable groups, which comprises about 45 to about 80% by mole of tetrafluoroethylene, about 50 to about 20% by mole of a perfluoro(vinylether) represented by the following general formula:CF.sub.2 .dbd.CFO(CF.sub.2).sub.2 (OCF.sub.2)nOCF.sub.3where n is an integer of 1 to 5, and about 0.2 to about 5% by mole of a bromine-containing unsaturated monomer compound, sum total being 100% by mole, gives vulcanization products having distinguished resistances to chemicals, low temperature and heat.

Abstract: 2,2 bis(3-mercaptophenyl)hexafluoropropane ?bisthiophenol AF! is obtained in good yield by chlorosulfonating 2,2'-bisphenylhexafluoropropane and reducing the thus quantitatively obtained 2,2'-bis(3-chlorosulfonylphenyl)hexafluoropropane with zinc under acidic conditions and is effectively used as a cross-linking agent for a fluorine-containing elastomer having halogenophenyl groups as cross-linkable groups.

Abstract: A fluorine-containing elastomer comprising vinylidene fluoride, tetrafluoroethylene and hexafluoropropylene having a high fluorine content (e.g. at least 68% by weight) can be vulcanized with a polyol-based cross-linking agent by further copolymerizing 2H-pentafluoropropylene into the elastomer, whereby the resulting vulcanization products having improved characteristics such as rheological properties, normal state physical properties and compression set can be obtained. Vulcanization products obtained by vulcanization with a polyol-based cross-linking agent and a quaternary onium salt compound have a good permeation resistance to fuel oil as a result of a permeation test with a mixed solvent of gasoline/methanol in a volume ratio of 85/15.

Abstract: A novel bisaminothiophenol compound represented by the following general formula: ##STR1## where Rf is a perfluoroalkylidene group having 1 to 10 carbon atoms, is used as a cross-linking agent for fluorine-containing elastomers having CN groups as cross-linkable groups.

Abstract: A fluorine-containing elastomer composition, which comprises a terpolymer of tetrafluoroethylene, perfluoro(lower alkyl vinyl ether) or perfluoro (lower alkoxy-lower alkyl vinyl ether) and cross-linkable cyano group-containing (perfluorovinylether), and a bis(aminothiophenol) compound represented by the following general formula as a cross-linking agent: ##STR1## wherein A is an alkylidene group having 1 to 6 carbon atoms, a perfluoroalkylidene group having 1 to 10 carbon atoms, a SO.sub.2 group, an O atom, a CO group or a carbon-carbon bond capable of directly bonding two benzene rings and one of X and Y is an amino group, while the other is a mercapto group, can produce cross-linked fluororubber moldings having an improved compression set.

Abstract: Perfluoroalkyleneethertriazine oligomer obtained by reacting a dinitrile compound NC--RF.sup.0 --CN where Rf.sup. is --(CFXOCF.sub.2)a(CF.sub.2)b(CF.sub.2 OCFX)c--, where X is a fluorine atom or a CF.sub.3 group, a is an integer of 1 to 5, b is an integer of 1 to 2 and c is an integer of 1 to 5, or Rf.sup.0 is --CF.sub.2 O(CF.sub.2 O)dCF.sub.2 --, where d is an integer of 1 to 8, with ammonia, further reacting the resulting diamizine compound with a dinitrile compound NC--Rf.sup.1 --CN, Rf.sup.1 has the same meaning as that for Rf.sup.0 or Rf.sup.1 is a perfluoroalkylene group having 4 to 8 carbon atoms thereby obtaining a perfluoroalkyleneetherpolyimidoylamizine oligomer, then reacting the resulting oligomer with a perfluoronitrile compound Rf.sup.2 CN, Rf.sup.2 is CF.sub.3 (OCF.sub.2)e-- where e is an integer of 3 to 10 thereby treating the terminal groups thereof, and then subjecting the resulting terminal-treated oligomer to a ring-closing reaction with a perfluoroacylating agent RF.sup.3 COY, Rf.sup.

Abstract: Perfluoroalkyleneethertriazine oligomer obtained by reacting a dinitrile compound NC--Rf.sup.0 --CN, where Ff.sup.0 is --(CFXOCF.sub.2)a(CF.sub.2)b(CF.sub.2 OCFX)c--, where X is a fluorine atom or a CF.sub.3 group, a is an integer of 1 to 5, b is an integer of 1 to 2 and c is an integer of 1 to 5, or Rf.sup.0 is --CF.sub.2 O(CF.sub.2 O)dCF.sub.2 --, where d is an integer of 1 to 8, with ammonia, further reacting the resulting diamizine compound with a dinitrile compound NC--RF.sup.1 --CN, RF.sup.1 has the same meaning as that for Rf.sup.0 or Rf.sup.1 is a perfluoroalkylene group having 4 to 8 carbon atoms thereby obtaining a perfluoroalkyleneetherpolyimidoyamizine oligomer, then reacting the resulting oligomer with a perfluoronitrile compound Rf.sup.2 CN, Rf.sup.2 is CF.sub.3 (OCF.sub.2).sub.e -- where e is an integer of 3 to 10 thereby treating the terminal groups thereof, and then subjecting the resulting terminal-treated oligomer to a ring-closing reaction with a perfluoroacylating agent RF.sup.3 COY, Rf.

Abstract: Filler-containing, cross-linked, vulcanized fluorine rubber waste is regenerated by treatment with at least one of CH.sub.3 SO.sub.3 H, ClSO.sub.3 H, CF.sub.3 SO.sub.3 H and fuming sulfuric acid, followed by dissoluting into a solvent and separating solvent-insoluble filler therefrom, whereby revulcanizable fluorine rubber is recovered from the fluorine rubber waste, almost irrespective of types of cross-linking systems used for formation of cross-linked, vulcanized fluorine rubber.

Abstract: A fluorine-containing elastomer composition, which comprises a terpolymer of tetrafluoroethylene, perfluoro(lower alkyl vinyl ether) and a perfluoro unsaturated nitrile compound represented by the following general formula:CF.sub.2 .dbd.CFO(CF.sub.2)nOCF(CF.sub.3)CN,wherein n is an integer of 2 to 5, and a bis(aminophenyl) compound represented by the following general formula as a cross-linking agent: ##STR1## wherein A is an alkylidene group having 1 to 6 carbon atoms or a perfluoroalkylidene group having 1 to 10 carbon atoms and X and Y are a hydroxyl group or an amino group, can produce vulcanized products having good vulcanization physical properties and a.good compression set.