Abstract: The present invention relates to a fluorine-containing diene compound represented by the following formula I, and to a polymer thereof. In the formula, each of R1 to R7 is independently a hydrogen atom, a chlorine atom, a fluorine atom, or an alkyl group having a carbon number of 1 to 5 which may be substituted by a fluorine atom, k is 0 or 1, and at least one of R1 to R7 is a hydrogen atom.

Abstract: To provide a method for producing a fluorinated polymer which enables stable production of a fluorinated polymer having a high molecular weight at a high polymerization rate with good productivity and reduced environmental burdens, a method for producing a fluorinated polymer having functional groups, and a method for producing an electrolyte membrane. A method for producing a fluorinated polymer, which comprises polymerizing a monomer mixture containing tetrafluoroethylene and a fluorinated monomer having a group convertible to a sulfonic acid group or a carboxylic acid group in a polymerization medium, wherein the polymerization medium contains as the main component a C4-10 cyclic hydrofluorocarbon. Further, a method for producing a fluorinated polymer having functional groups and a method for producing an electrolyte membrane, employing the production method.

Abstract: The present invention relates to a fluorine-containing diene compound represented by the following formula I, and to a polymer thereof. In the formula, each of R1 to R7 is independently a hydrogen atom, a chlorine atom, a fluorine atom, or an alkyl group having a carbon number of 1 to 5 which may be substituted by a fluorine atom, k is 0 or 1, and at least one of R1 to R7 is a hydrogen atom.

Abstract: To provide a method for producing a fluorinated polymer which enables stable production of a fluorinated polymer having a high molecular weight at a high polymerization rate with good productivity and reduced environmental burdens, a method for producing a fluorinated polymer having functional groups, and a method for producing an electrolyte membrane. A method for producing a fluorinated polymer, which comprises polymerizing a monomer mixture containing tetrafluoroethylene and a fluorinated monomer having a group convertible to a sulfonic acid group or a carboxylic acid group in a polymerization medium, wherein the polymerization medium contains as the main component a C4-10 cyclic hydrofluorocarbon. Further, a method for producing a fluorinated polymer having functional groups and a method for producing an electrolyte membrane, employing the production method.

Abstract: The purpose of the present invention is to obtain a fluorine-containing compound which is easily stabilized without irradiation of ultraviolet light, by efficiently converting a C—I bond in an iodine-containing compound having a group represented by —CFRf—I (wherein Rf is a fluorine atom or a perfluoroalkyl group) to a C—H bond. A method for producing a fluorine-containing compound having an iodine atom content reduced than the following iodine-containing compound, which comprises subjecting an iodine-containing compound having a group represented by —CFRf—I (wherein Rf is a fluorine atom or a perfluoroalkyl group) to deiodinating treatment in the presence of an organic peroxide and a hydrogen-containing compound having a group represented by —CHR1—CHR2—CHR3— (wherein R1, R2 and R3 are each independently a hydrogen atom or an alkyl group).

Abstract: The purpose of the present invention is to obtain a fluorine-containing compound which is easily stabilized without irradiation of ultraviolet light, by efficiently converting a C—I bond in an iodine-containing compound having a group represented by —CFRf—I (wherein Rf is a fluorine atom or a perfluoroalkyl group) to a C—H bond. A method for producing a fluorine-containing compound having an iodine atom content reduced than the following iodine-containing compound, which comprises subjecting an iodine-containing compound having a group represented by —CFRf—I (wherein Rf is a fluorine atom or a perfluoroalkyl group) to deiodinating treatment in the presence of an organic peroxide and a hydrogen-containing compound having a group represented by —CHR1—CHR2—CHR3— (wherein R1, R2 and R3 are each independently a hydrogen atom or an alkyl group).

Abstract: To provide a membrane/electrode assembly excellent in the power generation characteristics even under low or no humidity conditions or under high humidity conditions, and an electrolyte material suitable for a catalyst layer of the 5 membrane/electrode assembly, an electrolyte material is used which comprises a polymer (H) having a unit (A) which has an ion exchange group and in which all hydrogen atoms (excluding H+ of the ion exchange group) bonded to carbon atoms are substituted by fluorine atoms, a unit (B) which has a 5-membered ring and in which all hydrogen atoms bonded to carbon 10 atoms are substituted by fluorine atoms, and a unit (C) which has neither an ion exchange group nor a ring structure, has an ether bond, and has an ether equivalent of at most 350 as established by the following formula (I) and in which all hydrogen atoms bonded to carbon atoms are substituted by fluorine atoms: Ether equivalent=the molecular weight of the monomer forming the unit (C)/the 15 number of ether bonds in the mo

Abstract: To provide: an electrolyte material having high oxygen permeability as compared with conventional ones; a membrane electrode assembly for a polymer electrolyte fuel cell excellent in power generation characteristics as compared with conventional ones; a liquid composition suitable for forming a catalyst layer for the membrane electrode assembly; and a fluorinated branched polymer useful as e.g. a raw material of the electrolyte material. The electrolyte material comprises a fluoropolymer (H)1 having a structural unit (u1) that has an ionic group and a structural unit (u2) that has an alicyclic structure, wherein the fluoropolymer (H)1 is composed of a branched molecular chain, and has a segment (A)3 comprising a molecular chain having the structural unit (u1) and a segment (B)2 composed of a molecular chain having the structural unit (u2), and the ion exchange capacity of the segment (B)2 is smaller than the ion exchange capacity of the segment (A)3.

Abstract: It is to provide an electrolyte material with which an increase in the water content can be suppressed even when the ion exchange capacity of a polymer having repeating units based on a monomer having a dioxolane ring is high; and a membrane/electrode assembly excellent in the power generation characteristics under low or no humidity conditions and under high humidity conditions. It is to use an electrolyte material, which comprises a polymer (H) having ion exchange groups converted from precursor groups in a polymer (F), and having an ion exchange capacity of at least 1.35 meq/g dry resin, the polymer (F) having repeating units (A) based on a perfluoromonomer having a precursor group of an ion exchange group and a dioxolane ring and repeating units (B) based on a perfluoromonomer having no precursor group and having a dioxolane ring, and having a TQ of at least 200° C.

Abstract: To provide a membrane/electrode assembly excellent in the power generation characteristics even under low or no humidity conditions or under high humidity conditions, and an electrolyte material suitable for a catalyst layer of the membrane/electrode assembly.

Abstract: To provide a method for producing an organic compound having a sulfo group by efficiently hydrolyzing an organic compound having a fluorosulfonyl group with a small number of steps with a small quantity of waste liquid. A method for producing an organic compound having a sulfo group, which comprises bringing an organic compound having a fluorosulfonyl group into contact with subcritical water at from 200 to 320° C. to convert the fluorosulfonyl group into a sulfo group.

Abstract: To provide a method for producing an organic compound having a sulfo group by efficiently hydrolyzing an organic compound having a fluorosulfonyl group with a small number of steps with a small quantity of waste liquid. A method for producing an organic compound having a sulfo group, which comprises bringing an organic compound having a fluorosulfonyl group into contact with subcritical water at from 200 to 320° C. to convert the fluorosulfonyl group into a sulfo group.

Abstract: To provide an electrolyte polymer for polymer electrolyte fuel cells, made of a perfluorinated polymer having sulfonic groups, characterized in that in a test of immersing 0.1 g of the polymer in 50 g of a fenton reagent solution containing 3% of an aqueous hydrogen peroxide solution and 200 ppm of bivalent iron ions at 40° C. for 16 hours, the amount of eluted fluorine ions detected in the solution is not more than 0.002% of the total amount of fluorine in the polymer immersed. The electrolyte polymer of the present invention has very few unstable terminal groups and has an excellent durability, and therefore, is suitable as a polymer constituting an electrolyte membrane for polymer electrolyte fuel cells and a polymer contained in a catalyst layer.

Abstract: A fluorosulfonyl group-containing monomer having a high polymerization reactivity and plural fluorosulfonyl groups, a fluorosulfonyl group-containing polymer and a sulfonic acid group-containing polymer, obtained by using the monomer.

Abstract: An electrolyte material, which comprises a polymer (H) having ion exchange groups converted from precursor groups in a polymer (F) having repeating units (A) having a precursor group represented by the formula (g1) and repeating units (B) based on a perfluoromonomer having a 5-membered ring, and having a density of at most 2.03 g/cm3, the polymer (H) having an ion exchange capacity of from 1.3 to 2.3 meq/g dry resin: wherein Q1 and Q2 are a perfluoroalkylene group having an etheric oxygen atom, or the like, and Y is F or the like; the electrolyte material being suitable for a catalyst layer of the membrane/electrode assembly; the membrane/electrode assembly being excellent in power generation characteristics under low or no humidity conditions and under high humidity conditions.

Abstract: A fluorosulfonyl group-containing monomer having a high polymerization reactivity and plural fluorosulfonyl groups, a fluorosulfonyl group-containing polymer and a sulfonic acid group-containing polymer, obtained by using the monomer.

Abstract: A solid polymer electrolyte material made of a copolymer comprising a repeating unit based on a fluoromonomer A which gives a polymer having an alicyclic structure in its main chain by radical polymerization, and a repeating unit based on a fluoromonomer B of the following formula (1): CF2?CF(Rf)jSO2X??(1) wherein j is 0 or 1, X is a fluorine atom, a chlorine atom or OM {wherein M is a hydrogen atom, an alkali metal atom or a group of NR1R2R3R4 (wherein each of R1, R2, R3 and R4 which may be the same or different, is a hydrogen atom or a monovalent organic group)}, and Rf is a C1-20 polyfluoroalkylene group having a straight chain or branched structure which may contain ether oxygen atoms.

Abstract: A solid polymer electrolyte material made of a s copolymer comprising a repeating unit based on a fluoromonomer A which gives a polymer having an alicyclic structure in its main chain by radical polymerization, and a repeating unit based on a fluoromonomer B of the following formula (1): CF2?CF(Rf)jSO2X??(1) wherein j is 0 or 1, X is a fluorine atom, a chlorine atom or OM {wherein M is a hydrogen atom, an alkali metal atom or a group of NR1R2R3R4 (wherein each of R1, R2, R3 and R4 which may be the same or different, is a hydrogen atom or a monovalent organic group)}, and Rf is a C1-20 polyfluoroalkylene group having a straight chain or branched structure which may contain ether oxygen atoms.

Abstract: A solid polymer electrolyte material made of a copolymer comprising a repeating unit based on a fluoromonomer A which gives a polymer having an alicyclic structure in its main chain by radical polymerization, and a repeating unit based on a fluoromonomer B of the following formula (1): CF2?CF(Rf)jSO2X??(1) wherein j is 0 or 1, X is a fluorine atom, a chlorine atom or OM {wherein M is a hydrogen atom, an alkali metal atom or a group of NR1R2R3R4 (wherein each of R1, R2, R3 and R4 which may be the same or different, is a hydrogen atom or a monovalent organic group)}, and Rf is a C1-20 polyfluoroalkylene group having a straight chain or branched structure which may contain ether oxygen atoms.

Abstract: An electrolyte material for a polymer electrolyte fuel cell, which is made of a copolymer comprising repeating units based on CF2?CFCF2OCF2CF2SO3H and repeating units based on tetrafluoroethylene and which has an ion exchange capacity of from 0.9 to 1.5 (meq/g dry resin). This electrolyte material has ion conductivity and durability equal to conventional electrolyte material, is easy to synthesize, has a softening point higher than electrolyte material heretofore widely used for application to fuel cells and is suitable for operation of a polymer electrolyte fuel cell at a temperature higher than the conventional material.