Abstract: A fluorine-containing alloyed copolymer, which comprises a fluorine-containing elastomer copolymer having a fluorine content of not less than 64% by weight, and a resinous tetrafluoroethylene-perfluoro(alkyl vinyl ether) copolymer having an amount of heat of crystal fusion ?H of not more than 10 J/g, can give crosslinked moldings having a distinguished plasma resistance against both CF4 plasma treatment and O2 plasma treatment, and also a distinguished cracking resistance at the plasma irradiation, and showing necessary normal state physical properties and compression set when used as seals, and capable of providing soft seals of low hardness, and attaining molding at relatively low temperatures.

Abstract: A polyfluoroalkane carboxylic acid represented by the following general formula: CnF2n+1(CH2CF2)m(CF2CF2)l?1CF2COOM (M: an alkali metal, a NH4 group or H; n: an integer of 1 to 6; m: an integer of 1 to 4; and l: 1 or 2) can be produced by hydrolysis reaction of polyfluoroalkane carboxylic acid fluoride represented by the following general formula: CnF2n+1(CH2CF2)m(CF2CF2)l?1CF2COF, where its carboxylic acid salt can be formed as an alkali metal salt, or a NH4 salt. The polyfluoroalkane carboxylic acid (or its salt) can act as a surfactant having distinguished monomer emulsifiability and latex stability when used as an emulsifying agent or as a dispersing agent for polymerization reaction of fluorine-containing monomers, or as an effective surfactant capable of enhancing the micelles solubility of fluorine-containing monomers such as vinylidene fluoride, etc., when used as an emulsifying agent or a dispersing agent for homopolymerization or copolymerization reaction of vinylidene fluoride.

Abstract: A polyfluoroalkane carboxylic acid represented by the following general formula: CnF2n+1(CH2CF2)m(CF2CF2)l?1CF2COOM (M: an alkali metal, a NH4 group or H; n: an integer of 1 to 6; m: an integer of 1 to 4; and l: 1 or 2) can be produced by hydrolysis reaction of polyfluoroalkane carboxylic acid fluoride represented by the following general formula: CnF2n+1(CH2CF2)m(CF2CF2)l?1CF2COF , where its carboxylic acid salt can be formed as an alkali metal salt, or a NH4 salt. The polyfluoroalkane carboxylic acid (or its salt) can act as a surfactant having distinguished monomer emulsificability and latex stability when used as an emulsifying agent or as a dispersing agent for polymerization reaction of fluorine-containing monomers, or as an effective surfactant capable of enhancing the micelles solubility of fluorine-containing monomers such as vinylidene fluoride, etc., when used as an emulsifying agent or a dispersing agent for homopolymerization or copolymerization reaction of vinylidene fluoride.

Abstract: A fluorine-containing elastomer having a copolymer composition, which comprises (a) 50-85 mol. % of vinylidene fluoride, (b) 0-25 mol. % of tetrafluoroethylene, (c) 7-20 mol. % of perfluoro(methyl vinyl ether), (d) 2.5-15 mol. % of CF2?CFO[CF2CF(CF3)O]nCF3 (n: 2-6), (e) 0.1-2 mol. % of CF2?CFO[CF2CF(CF3)O]mCF2CF3 (m: 2-6), and (f) 0.1-2 mol. % of RfX (Rf: an unsaturated fluorohydrocarbon group having 2-8 carbon atoms, which can contain at least one ether bond, X: bromine or iodine), can provide a fluorine-containing elastomer composition, which comprises 100 parts by weight of the fluorine-containing elastomer, 0.1-10 parts by weight of an organic peroxide, 0.1-10 parts by weight of a polyfunctional unsaturated compound, and at least 2 parts by weight of an acid acceptor. The composition can give vulcanizates having a distinguished elongation at break at high temperatures such as 100° C., and distinguished compression set characteristics at low temperatures such as 0° C.

Abstract: A fluoroelastomer is produced by the polymerization reaction of a fluorinated olefin using a ?H perfluorocarboxylic acid represented by the general formula: H(CF2)nCOOM (wherein M is hydrogen atom, alkali metal, or ammonium group; and n is 6, 7, or 8) or a salt thereof, as an emulsifier. The fluoroelastomer produced by the method of the present invention has a low Mooney viscosity ML1+10(121° C.) and thereby has an improved fluidity, which is essential for injection molding materials, as a result of the polymerization reaction of a fluorinated olefin using a ?H perfluorocarboxylic acid (salt) as an emulsifier. Accordingly, the productivity in injection molding can be improved. Moreover, there is neither remarkable decrease in the polymerization rate of the polymerization reaction nor deterioration of the physical properties of the vulcanizate, such as tensile strength, compression set characteristics, and hot tear resistance.

Abstract: A fluorine-containing elastomer having a copolymer composition, which comprises (a) 50-85 mol. % of vinylidene fluoride, (b) 0-25 mol. % of tetrafluoroethylene, (c) 7-20 mol. % of perfluoro(methyl vinyl ether), (d) 2.5-15 mol. % of CF2?CFO[CF2CF(CF3)O]nCF3 (n: 2-6), (e) 0.1-2 mol. % of CF2?CFO[CF2CF(CF3)O]mCF2CF3 (m: 2-6), and (f) 0.1-2 mol. % of RfX (Rf: an unsaturated fluorohydrocarbon group having 2-8 carbon atoms, which can contain at least one ether bond, X: bromine or iodine), can provide a fluorine-containing elastomer composition, which comprises 100 parts by weight of the fluorine-containing elastomer, 0.1-10 parts by weight of an organic peroxide, 0.1-10 parts by weight of a polyfunctional unsaturated compound, and at least 2 parts by weight of an acid acceptor. The composition can give vulcanizates having a distinguished elongation at break at high temperatures such as 100° C., and distinguished compression set characteristics at low temperatures such as 0° C.

Abstract: A fluorine-containing alloyed copolymer, which comprises a fluorine-containing elastomer copolymer having a fluorine content of not less than 64% by weight, and a resinous tetrafluoroethylene-perfluoro(alkyl vinyl ether) copolymer having an amount of heat of crystal fusion ?H of not more than 10 J/g, can give crosslinked moldings having a distinguished plasma resistance against both CF4 plasma treatment and O2 plasma treatment, and also a distinguished cracking resistance at the plasma irradiation, and showing necessary normal state physical properties and compression set when used as seals, and capable of providing soft seals of low hardness, and attaining molding at relatively low temperatures.

Abstract: A fluorine-containing copolymer, which comprises a hydroxyl-terminated fluorine-containing vinyl ether, represented by the following general formula: CF2?CFORfCH2OH (where Rf is a fluoroalkylene group, a fluoroalkyl ether group, or a fluoroalkoxyfluoroalkyl ether group, having 1-25 carbon atoms), and at least one of other fluorine-containing unsaturated monomers, where a high-molecular weight fluorine-containing copolymer having a melt viscosity (230° C.) of 0.1-100 g/10 min. is insoluble in a solvent, and can be used suitably for melt molding, whereas a low-molecular weight fluorine-containing copolymer having a glass transition temperature Tg of 20° C., or higher, and a number average molecular weight Mn of 1,000, or more is soluble in a solvent, and can be used suitably for coating agents, etc.

Abstract: A fluorine-containing copolymer, which comprises a hydroxyl-terminated fluorine-containing vinyl ether, represented by the following general formula: CF2?CFORfCH2OH (where Rf is a fluoroalkylene group, a fluoroalkyl ether group, or a fluoroalkoxyfluoroalkyl ether group, having 1-25 carbon atoms), and at least one of other fluorine-containing unsaturated monomers, where a high-molecular weight fluorine-containing copolymer having a melt viscosity (230° C.) of 0.1-100 g/10 min. is insoluble in a solvent, and can be used suitably for melt molding, whereas a low-molecular weight fluorine-containing copolymer having a glass transition temperature Tg of 20° C., or higher, and a number average molecular weight Mn of 1,000, or more is soluble in a solvent, and can be used suitably for coating agents, etc.

Abstract: A cross-linked fluorine-containing copolymer moldings applicable to a plasma irradiation step, which is molded as a peroxide cross-linking product of a fluorine-containing copolymer blend comprising a fluorine-containing elastomer copolymer and a fluorine-containing resin copolymer, which is a vinylidene fluoride-tetrafluoroethylene copolymer, both of the copolymers having reaction sites capable of reacting with a common peroxide-based cross-linking agent, respectively, has desired normal state physical properties and compression set value, even if applied to a plasma irradiation step, while reducing particle generation quantity of the fluorine-containing copolymers themselves.

Abstract: A process for preparing a fluorine-containing copolymer by an emulsion polymerization method in the presence of aqueous ammonia as a pH modifier, and a molded article obtainable by melt molding or crosslinking molding the fluorine-containing copolymer. In preparing the fluorine-containing copolymer by coagulation of the fluorine-containing copolymer contained in a fluorine-containing copolymer dispersed aqueous solution, it is preferred to use a cationic surfactant and a water soluble organic solvent as a coagulating agent used for the above coagulation. The surfactant is preferably represented by the, formula (R4N+)X? wherein R is an alkyl group of 1 to 22 carbon atoms, a fluoroalkyl group obtainable by fluorine substituting at least a part of hydrogen atoms present in the above alkyl group or hydrogen, four R's may be the same or different provided that they are not hydrogen atoms simultaneously, and X is a halogen atom.

Abstract: A fluorine-containing copolymer, which comprises a hydroxyl-terminated fluorine-containing vinyl ether, represented by the following general formula: CF2?CFORfCH2OH (where Rf is a fluoroalkylene group, a fluoroalkyl ether group, or a fluoroalkoxyfluoroalkyl ether group, having 1-25 carbon atoms), and at least one of other fluorine-containing unsaturated monomers, where a high-molecular weight fluorine-containing copolymer having a melt viscosity (230° C.) of 0.1-100 g/10 min. is insoluble in a solvent, and can be used suitably for melt molding, whereas a low-molecular weight fluorine-containing copolymer having a glass transition temperature Tg of 20° C., or higher, and a number average molecular weight Mn of 1,000, or more is soluble in a solvent, and can be used suitably for coating agents, etc.

Abstract: A process for preparing a fluorine containing copolymer by an emulsion polymerization method in the presence of aqueous ammonia as a pH modifier, and a molded article obtainable by melt molding or crosslinking molding the fluorine containing copolymer are disclosed. In preparing the fluorine containing copolymer by coagulation of the fluorine containing copolymer contained in a fluorine containing copolymer dispersed aqueous solution, it is preferred to use a cationic surfactant and a water soluble organic solvent as a coagulating agent used for the above coagulation. The surfactant is preferably represented by the formula (R4N+)X? wherein R is an alkyl group of 1 to 22 carbon atoms, a fluoroalkyl group obtainable by fluorine substituting at least a part of hydrogen atoms present in the above alkyl group or hydrogen, four R's may be the same or different provided that they are not hydrogen atoms simultaneously, and X is a halogen atom.

Abstract: A fluorine-containing terpolymer with distinguished transparency and strength at ordinary temperature and at elevated temperatures when heated, which comprises 20–98% by weight of tetrafluoroethylene, 1–40% by weight of perfluoro(ethyl vinyl ether) and 1–40% by weight of perfluoro(propyl vinyl ether) and has a specific melt viscosity of 0.1×103–110×103 Pa·s (372° C.). The fluorine-containing terpolymer preferably has a comonomer ratio of perfluoro(propyl vinyl ether) to perfluoro(ethyl vinyl ether) of 1.0 or more by weight.

Abstract: A fluoropolymer molding, which comprises a perfluoropolymer capable of undergoing low-temperature melt molding and having a calorimetric value of crystal fusion of not more than 10 J/g and an MFR (230° C.) of 0.1 to 100 g/min. the molding having a surface modified to have bonds of nitrogen atom origin, where the modification to the surface having bonds of nitrogen atom origin is carried out by electric discharge treatment in an ammonia gas atmosphere. The thus obtained perfluoropolymer molding with a high fluorine content of not less than 72 wt. % can be easily formed into a laminate with other substrates.

Abstract: A fluorine-containing terpolymer with distinguished transparency and strength at ordinary temperature and at elevated temperatures when heated, which comprises 20-98% by weight of tetrafluoroethylene, 1-40% by weight of perfluoro(ethyl vinyl ether) and 1-40% by weight of perfluoro(propyl vinyl ether) and has a specific melt viscosity of 0.1×103-110×103 Pa·s (372° C.). The fluorine-containing terpolymer preferably has a comonomer ratio of perfluoro(propyl vinyl ether) to perfluoro(ethyl vinyl ether) of 1.0 or more by weight.

Abstract: Vinylidene fluoride and chlorotrifluoroethylene are copolymerized in the presence of a compound represented by the general formula I: InBrmR  (I) wherein R represents a fluorohydrocarbon group, a chlorofluorohydrocarbon group, a chlorohydrocarbon group or a hydrocarbon group, and n is 0, 1 or 2 and m is 0, 1 or 2 provided that n+m≧2. This provides a process for producing a fluorinated copolymer which enables providing a fluorinated copolymer crosslinking product having mechanical properties satisfactory for practical use as sealants even if no inorganic additive is added thereto.

Abstract: A fluorine-containing copolymer composition comprising a fluorine-containing elastomer and a fluororesin, both having reaction sites capable of reacting with a common crosslinking agent gives crosslinking molding products having distinguished roll processability, moldability and mechanical strength, where crosslinking molding is carried out preferably by a peroxide crosslinking system or polyol crosslinking system, and the low temperature characteristics is considerably improved when the fluororesin has a softening point of not less than 120.degree. C.

Abstract: A fluorine-containing graft copolymer produced by copolymerizing at least two kinds of monomers selected from the group consisting of fluorinated monomers and propylene in the presence of a saturated iodine-containing compound or an iodine and bromine-containing compound, and further graft copolymerizing the resulting copolymer with tetrafluoroethylene and polyfluorovinyl ether represented by the general formula:CF.sub.2 .dbd.CFOCX.sub.2 (CF.sub.2).sub.p Y(where X is H or F, Y is H or F and p is 0-3), where an unsaturated iodine-containing compound or an unsaturated bromine-containing compound may be used together with the saturated iodine-containing compound or iodine and bromine-containing compound. The resulting fluorine-containing graft copolymer is a thermoplastic fluorine-containing copolymer elastomer capable of giving molding products having a distinguished compression set in a high temperature region such as about 280.degree. C.

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.