Abstract: A fluorine-containing elastomer composition assuring a low compression set and comprising a perfluoroelastomer (A) comprising (a) 18 to 33% by mole of a perfluoro(alkyl vinyl ether) unit, (b) 0.3 to 0.6% by mole of a monomer unit having at least one selected from the group consisting of a nitrile group, a carboxyl group and an alkoxycarbonyl group and (c) a tetrafluoroethylene unit.

Abstract: There is provided a curable fluorine-containing polymer composition which is quickly cured at relatively low temperatures by hydrosilylation reaction and provides a coating film which has high hardness, excellent solvent resistance and flexibility. The curable fluorine-containing polymer composition comprises a fluorine-containing polymer comprising a fluorinated ethylenic monomer unit and a non-fluorinated ethylenic monomer unit, in which a part or the whole of the non-fluorinated ethylenic monomer units is a unit represented by the formula: wherein R1 is hydrogen or methyl; R2 is a hydrocarbon group having ethylenic C?C; X is —C(O)NH— or —C(O)—; R3 is —O—, —O[CH(R4)]mO—, —(CH2)mO—, —OC(O)—(CH2)mO— or —(CH2)mOC(O)—(CH2)nO—, where R4 is —H, —OH, —CH2OH or —O—X—R2, a siloxane compound having hydrogen atom bonded to silicon atom, and a catalyst for hydrosilylation reaction.

Abstract: The present invention provides a graft or a block polymer in which a fluorine rubber and a silicone rubber are chemically bonded. The present invention is a graft or a block polymer comprising at least one kind of a silicone rubber segment and at least one kind of a fluorine elastomer segment. Furthermore, it is preferable that a fluorine containing elastomer segment is an elastomer segment comprising vinylidene fluoride or an elastomer segment comprising tetrafluoroethylene and that a silicone rubber segment has a unit of dimethylsiloxane and/or methyl-3,3,3-trifluoropropylsiloxane.

Abstract: The invention provides a fluoropolymer composition capable of improving the characteristics of the cured material obtained therefrom. A fluoropolymer composition comprising a methylene group-containing fluoropolymer (A) and a hydrosilylation catalyst (B), wherein the methylene group-containing fluoropolymer (A) has methylene group-containing repeating units in the main chain thereof and is capable of hydrosilylation in the presence of the hydrosilylation catalyst (B) and one terminus of the chain is a carbon-carbon double bond or an Si—H group and the other terminus of the chain is an Si—H group or a carbon-carbon double bond.

Abstract: The present invention has for its object to provide a fluorocopolymer which is available at low cost, has fluidity at room temperature, and is curable, a method of producing the same copolymer and a curable composition having good processability and in situ moldability. The present invention is directed to a fluorocopolymer which is fluid at room temperature and curable, and which is obtainable from a trifluorovinyl group-containing monomer with an ethylenically unsaturated double bond moiety being a trifluorovinyl group.

Abstract: The invention provides a fluoropolymer composition capable of improving the characteristics of the cured material obtained therefrom. A fluoropolymer composition comprising a methylene group-containing fluoropolymer (A) and a hydrosilylation catalyst (B), wherein the methylene group-containing fluoropolymer (A) has methylene group-containing repeating units in the main chain thereof and is capable of hydrosilylation in the presence of the hydrosilylation catalyst (B) and one terminus of the chain is a carbon-carbon double bond or an Si—H group and the other terminus of the chain is an Si—H group or a carbon-carbon double bond.

Abstract: The present invention includes crosslinked perfluoroelastomeric compositions and molded articles formed from a cross-linkable perfluoroelastomeric composition having a first curable perfluoropolymer having a cure site monomer and a second perfluoropolymer having a cure site monomer. The molar ratio of the tetrafluoroethylene monomer to perfluoroalkylvinyl ether in one perfluoropolymer is about 0 to 100 to about 65 to 35 in the perfluoropolymer. The molar ratio of the tetrafluoroethylene monomer to the perfluoroalkylvinyl ether monomer in the second polymer is about 65:35 to about 95:5 in the second perfluoropolymer. The composition further includes a curative.

Abstract: The present invention has for its object to provide a fluorocopolymer which is available at low cost, has fluidity at room temperature, and is curable, a method of producing the same copolymer and a curable composition having good processability and in situ moldability. The present invention is directed to a fluorocopolymer which is fluid at room temperature and curable, and which is obtainable from a trifluorovinyl group-containing monomer with an ethylenically unsaturated double bond moiety being a trifluorovinyl group.

Abstract: The present invention provides a graft or a block polymer in which a fluorine rubber and a silicone rubber are chemically bonded. The present invention is a graft or a block polymer comprising at least one kind of a silicone rubber segment and at least one kind of a fluorine elastomer segment. Furthermore, it is preferable that a fluoirne containing elastomer segment is an elastomer segment comprising vinylidene fluoride or an elastomer segment comprising tetrafluoroethylene and that a silicone rubber segment has a unit of dimethylsiloxane and/or methyl-3,3,3-trifluoropropylsiloxane.

Abstract: The present invention has for its object to provide a fluorocopolymer which is available at low cost, has fluidity at room temperature, and is curable, a method of producing the same copolymer and a curable composition having good processability and in situ moldability. The present invention is directed to a fluorocopolymer which is fluid at room temperature and curable, and which is obtainable from a trifluorovinyl group-containing monomer with an ethylenically unsaturated double bond moiety being a trifluorovinyl group.

Abstract: The invention provides a fluoropolymer composition capable of improving the characteristics of the cured material obtained therefrom. A fluoropolymer composition comprising a methylene group-containing fluoropolymer (A) and a hydrosilylation catalyst (B), wherein the methylene group-containing fluoropolymer (A) has methylene group-containing repeating units in the main chain thereof and is capable of hydrosilylation in the presence of the hydrosilylation catalyst (B) and one terminus of the chain is a carbon-carbon double bond or an Si—H group and the other terminus of the chain is an Si—H group or a carbon-carbon double bond.

Abstract: The present invention provides an ethylene-hexafluoropropylene copolymer which is suitable as a hose or seal for engine oil of an automobile and has sufficient amine resistance, while maintaining heat resistance, oil resistance and chemical resistance close to that of conventional fluorine rubber. The ethylene-hexafluoropropylene copolymer comprises 35 to 60% by mole of ethylene structural unit, 25 to 50% by mole of hexafluoropropylene structural unit and 0 to 15% by mole of structural unit derived from a monomer copolymerizable therewith and has a fluorine content of at least 60% by weight and number average molecular weight of 3,000 to 500,000.

Abstract: To provide a method of reducing contents of metal components of a fluorine-containing elastomer through preparation thereof and a molded article obtained from the fluorine-containing elastomer having sufficiently reduced contents of metal components. The method of reducing a metal content of the fluorine-containing elastomer through preparation thereof without using a metal oxide, in which among materials excluding a gaseous monomer which are used for polymerization of a fluorine-containing monomer, coagulation and drying, at least one of them contains substantially no metal component, and the fluorine-containing elastomer which has a metal content of not more than 50 ppm and is obtained by that method.

Abstract: The present invention relates to a process for preparing an elastomeric ethylene-hexafluoropropylene copolymer with excellent vulcanization properties, which comprises emulsion polymerizing ethylene, hexafluoropropylene and when in demand, a monomer copolymerizable therewith in a aqueous medium at a low temperature of ?20° C. to 40° C. using a radical polymerization initiator.

Abstract: The present invention provides a fluorine-containing elastomer molded article, which is capable of withstanding use in high temperatures of 275° C. or higher and has resistance to high density plasma. Specifically, the present invention provides a fluorine-containing elastomer molded article obtained by crosslinking with a heat resistant crosslinking agent a crosslinkable fluorine-containing elastomer composition comprising an inorganic filler having a average primary particle size of at most 0.5 ?m, such as ?-type aluminum oxide and aluminum nitride, and a fluorine-containing elastomer component having a CN group or a COOH group, such as a perfluoro elastomer.

Abstract: According to the present invention, ethylene, HFP and when in demand, a monomer copolymerizable therewith can be emulsion polymerized at a low temperature of −20° C. to 40° C. at a high polymerization rate. Furthermore, the obtained elastomeric E-HFP copolymer has few branches and is excellent in processability.

Abstract: To provide a method of reducing contents of metal components of a fluorine-containing elastomer through preparation thereof and a molded article obtained from the fluorine-containing elastomer having sufficiently reduced contents of metal components. The method of reducing a metal content of the fluorine-containing elastomer through preparation thereof without using a metal oxide, in which among materials excluding a gaseous monomer which are used for polymerization of a fluorine-containing monomer, coagulation and drying, at least one of them contains substantially no metal component, and the fluorine-containing elastomer which has a metal content of not more than 50 ppm and is obtained by that method.

Abstract: To provide a method of reducing contents of metal components of a fluorine-containing elastomer through preparation thereof and a molded article obtained from the fluorine-containing elastomer having sufficiently reduced contents of metal components. The method of reducing a metal content of the fluorine-containing elastomer through preparation thereof without using a metal oxide, in which among materials excluding a gaseous monomer which are used for polymerization of a fluorine-containing monomer, coagulation and drying, at least one of them contains substantially no metal component, and the fluorine-containing elastomer which has a metal content of not more than 50 ppm and is obtained by that method.

Abstract: The present invention provides an ethylene-hexafluoropropylene copolymer which is suitable as a hose or seal for engine oil of an automobile and has sufficient amine resistance, while maintaining heat resistance, oil resistance and chemical resistance close to that of conventional fluorine rubber. The ethylene-hexafluoropropylene copolymer comprises 35 to 60% by mole of ethylene structural unit, 25 to 50% by mole of hexafluoropropylene structural unit and 0 to 15% by mole of structural unit derived from a monomer copolymerizable therewith and has a fluorine content of at least 60% by weight and number average molecular weight of 3,000 to 500,000.

Abstract: In the emulsion obtained by forcedly emulsifying by applying a high shearing force on the water insoluble liquid in the presence of a small amount of emulsifying agent, at least one of fluorine-containing monomers being in the form of gas at ordinary temperature at atmospheric pressure is emulsion-polymerized stably and efficiently. An amount of the emulsifying agent is an amount which does not change the number of water insoluble liquid particles in the emulsion during the polymerization.