Abstract: A tetrafluoroethylene/hexafluoropropylene copolymer has improved moldability in melt extrusion molding, especially with significant reduction of defects in high-speed extrusion coating of an electrical wire. The tetrafluoroethylene/hexafluoropropylene copolymer is obtained by polymerization of at least tetrafluoroethylene and hexafluoropropylene selected from the group consisting of tetrafluoroethylene, hexafluoropropylene and a third monomer without mixing with the resin which has the melting point with the difference of 20 degree C. and more from the melting point of the tetrafluoroethylene/hexafluoropropylene copolymer; and has a complex viscosity of from 2.0×I03 to 10.0×I03 Pa*s and a storage modulus of from 0.1 to 3.5 Pa*s in melt viscoelasticity measurement under the condition of atmosphere temperature of 310 degree C. and angular frequency of 0.01 radian/second. The tetrafluoroethylene/hexafluoropropylene copolymer can be used in an electrical wire as a coating on a conductive core.

Abstract: The present invention provides a method for producing a stabilized fluoropolymer which comprises producing the stabilized fluoropolymer by subjecting a treatment target substance containing a sulfonic-acid-derived-group-containing fluoropolymer to a fluorination treatment, wherein the sulfonic-acid-derived-group-containing fluoropolymer is a fluoropolymer containing —SO3M (in which M represents H, NR1R2R3R4 or M11/L; R1, R2, R3 and R4 are the same or different and each represents H or an alkyl group containing 1 to 4 carbon atoms; and M1 represents an L-valent metal), and the treatment target substance has a moisture content of not higher than 500 ppm by mass.

Abstract: A method of producing a fluororesin composition includes copolymerizing at least tetrafluoroethylene with hexafluoropropylene so that a melt flow rate at 372 degree C. of the copolymer formed in the copolymerization changes from 0.05-5.0 grams/10 minutes to 10-60 grams/10 minutes. The tetrafluoroethylene/hexafluoropropylene copolymer can be used as a coating on an electrical wire.

Abstract: The invention provides a technique enabling the separation and recovery of an unreacted fluoromonomer from an aqueous fluoropolymer dispersion obtained by emulsion polymerization, without using any extraction solvent, and enabling the prevention of a hydrolysis of —SO2F and a like sulfonic acid precursor functional group convertible to sulfonic acid group. Thus, the invention provides a recovering method fluoromonomer having a sulfonic acid precursor functional group convertible to a sulfonic acid group and remaining unreacted from an aqueous fluoropolymer dispersion obtained by emulsion polymerization of the fluoromonomer, wherein the unreacted fluoromonomer is recovered from the aqueous fluoropolymer dispersion by evaporation, wherein the aqueous fluoropolymer dispersion has an acidic pH.

Abstract: The present invention provides a novel production process by which unstable terminal groups can be sufficiently stabilized under mild conditions. The present invention is related to a method for producing an —SO3H group-containing fluoropolymer wherein a fluoropolymer to be treated having a —SO2X group-containing monomer unit (X representing F or Cl) is subjected to a procedure comprising at least the steps A, B and C defined below in that order: A: Step of reacting with a halogenating agent; B: Step of reacting with a decomposition treatment agent; C: Step of reacting with a fluorinating agent.

Abstract: The present invention provides a method for producing a stabilized fluoropolymer which comprises producing the stabilized fluoropolymer by subjecting a treatment target substance containing a sulfonic-acid-derived-group-containing fluoropolymer to a fluorination treatment, wherein the sulfonic-acid-derived-group-containing fluoropolymer is a fluoropolymer containing —SO3M (in which M represents H, NR1R2R3R4 or M11/L; R1, R2, R3 and R4 are the same or different and each represents H or an alkyl group containing 1 to 4 carbon atoms; and M1 represents an L-valent metal), and the treatment target substance has a moisture content of not higher than 500 ppm by mass.

Abstract: A tetrafluoroethylene/hexafluoropropylene copolymer has improved moldability in melt extrusion molding, especially with significant reduction of defects in high-speed extrusion coating of an electrical wire. The tetrafluoroethylene/hexafluoropropylene copolymer is obtained by polymerization of at least tetrafluoroethylene and hexafluoropropylene selected from the group consisting of tetrafluoroethylene, hexafluoropropylene and a third monomer without mixing with the resin which has the melting point with the difference of 20 degree C. and more from the melting point of the tetrafluoroethylene/hexafluoropropylene copolymer; and has a complex viscosity of from 2.0×I03 to 10.0×I03 Pa*s and a storage modulus of from 0.1 to 3.5 Pa*s in melt viscoelasticity measurement under the condition of atmosphere temperature of 310 degree C. and angular frequency of 0.01 radian/second. The tetrafluoroethylene/hexafluoropropylene copolymer can be used in an electrical wire as a coating on a conductive core.

Abstract: The present invention provides a novel production process by which unstable terminal groups can be sufficiently stabilized under mild conditions. The present invention is related to a method for producing an —SO3H group-containing fluoropolymer wherein a fluoropolymer to be treated having a —SO2X group-containing monomer unit (X representing F or Cl) is subjected to a procedure comprising at least the steps A, B and C defined below in that order: A: Step of reacting with a halogenating agent; B: Step of reacting with a decomposition treatment agent; C: Step of reacting with a fluorinating agent.

Abstract: The present invention provides a novel production process by which unstable terminal groups can be sufficiently stabilized under mild conditions. The present invention is related to a method for producing an —SO3H group-containing fluoropolymer wherein a fluoropolymer to be treated having a —SO2X group-containing monomer unit (X representing F or Cl) is subjected to a procedure comprising at least the steps A, B and C defined below in that order: A: Step of reacting with a halogenating agent; B: Step of reacting with a decomposition treatment agent; C: Step of reacting with a fluorinating agent.

Abstract: The invention provides a technique enabling the separation and recovery of an unreacted fluoromonomer from an aqueous fluoropolymer dispersion obtained by emulsion polymerization, without using any extraction solvent, and enabling the prevention of a hydrolysis of —SO2F and a like sulfonic acid precursor functional group convertible to sulfonic acid group. Thus, the invention provides a recovering method fluoromonomer having a sulfonic acid precursor functional group convertible to a sulfonic acid group and remaining unreacted from an aqueous fluoropolymer dispersion obtained by emulsion polymerization of the fluoromonomer, wherein the unreacted fluoromonomer is recovered from the aqueous fluoropolymer dispersion by evaporation, wherein the aqueous fluoropolymer dispersion has an acidic pH.

Abstract: The present invention provides a novel production process by which unstable terminal groups can be sufficiently stabilized under mild conditions. The present invention is related to a method for producing an —SO3H group-containing fluoropolymer wherein a fluoropolymer to be treated having a —SO2X group-containing monomer unit (X representing F or Cl) is subjected to a procedure comprising at least the steps A, B and C defined below in that order: A: Step of reacting with a halogenating agent; B: Step of reacting with a decomposition treatment agent; C: Step of reacting with a fluorinating agent.

Abstract: The present invention relates to a method for producing a fluorocopolymer which comprises a polymerization reaction of a fluorine-containing ethylenic monomer with a fluorovinyl ether derivative represented by the following general formula (I): CF2?CF—O—[CF2CF(CF3)O]n—(CF2)m-A??(I) (wherein n represents an integer of 0 to 3, m represents an integer of 1 to 5, and A represents —SO2X or —COOY; X represents a halogen atom or —NR1R2; R1 and R2 are the same or different and each represents a hydrogen atom, an alkali metal, an alkyl group or a sulfonyl-containing group and Y represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms) to give a fluorocopolymer, said fluorine-containing ethylenic monomer being a perhaloethylenic monomer represented by the following general formula (II): CF2?CF—Rf1??(II) (wherein Rf1 represents a fluorine atom, a chlorine atom, Rf2 or ORf2; Rf2 represents a straight or branched perfluoroalkyl group having 1 to 9 carbon atoms, which may have an ether oxygen atom(s)) a

Abstract: The present invention relates to a method of producing the fluoropolymer according to any one of claims 1 to 3, by subjecting a fluoropolymer precursor containing acid/acid salt groups and having —CF2COOX groups at polymer chain terminals, in the formula X represents H, NR11R12R13R14 or M41/L; R11, R12, R13 and R14 are the same or different and each represents H or an alkyl group containing 1 to 4 carbon atoms and M4 represents a metal having a valence of L, said metal having a valence of L being a metal belonging to the group 1, 2, 4, 8, 11, 12 or 13 of the long-form periodic table, to heat treatment for the conversion of said —CF2COOX groups to —CF2H groups, X being as defined above, wherein said fluoropolymer precursor is one obtained by polymerizing a perhalovinyl ether derivative represented by the general formula (I): CF2?CF—O—(CF2CFY1—O)n—(CFY2)m—SO2Z ??(I) wherein Y1 represents F, Cl or a perfluoroalkyl group, n represents an integer of 0 to 3, the n atoms/groups of Y1 are the same or different, Y2

Abstract: The present invention provides a method for producing a stabilized fluoropolymer which comprises producing the stabilized fluoropolymer by subjecting a treatment target substance containing a sulfonic-acid-derived-group-containing fluoropolymer to a fluorination treatment, wherein the sulfonic-acid-derived-group-containing fluoropolymer is a fluoropolymer containing —SO3M (in which M represents H, NR1R2R3R4 or M11/L; R1, R2, R3 and R4 are the same or different and each represents H or an alkyl group containing 1 to 4 carbon atoms; and M1 represents an L-valent metal), and the treatment target substance has a moisture content of not higher than 500 ppm by mass.

Abstract: The present invention relates to a method for producing a fluorocopolymer which comprises a polymerization reaction of a fluorine-containing ethylenic monomer with a fluorovinyl ether derivative represented by the following general formula (I): CF2?CF—O—[CF2CF(CF3)O]n—(CF2)m-A??(I) (wherein n represents an integer of 0 to 3, m represents an integer of 1 to 5, and A represents —SO2X or —COOY; X represents a halogen atom or —NR1R2; R1 and R2 are the same or different and each represents a hydrogen atom, an alkali metal, an alkyl group or a sulfonyl-containing group and Y represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms) to give a fluorocopolymer, said fluorine-containing ethylenic monomer being a perhaloethylenic monomer represented by the following general formula (II): CF2?CF—Rf1??(II) (wherein Rf1 represents a fluorine atom, a chlorine atom, Rf2 or ORf2; Rf2 represents a straight or branched perfluoroalkyl group having 1 to 9 carbon atoms, which may have an ether oxygen atom(s)) an