Abstract: The present invention provides a process for producing a fluorinated ionomer, comprising copolymerizing, in the presence of a polymerization initiator, (i) a compound represented by Formula (I) (M)1/LOSO2CFY(CF2)mO(CFXCF2O)nCF?CF2??(I) wherein M is H or a metal with a valence of L (L is 1, 2 or 3), X is F, Cl or CF3, Y is halogen, m is 1 to 5, and n is 0 to 5, (ii) tetrafluoroethylene and (iii) at least one third monomer selected from the group consisting of hexafluoropropylene, chlorotrifluoroethylene, vinylidene fluoride, CF2?CFORf (Rf is C1 to C5 perfluoroalkyl) and ethylene. The present invention further provides a method for purifying and concentrating a fluorinated ionomer, comprising ultrafiltration or dialysis of a fluorinated ionomer solution or dispersion, and a method for forming a film of the fluorinated ionomer.

Abstract: An electrode additive comprising an aqueous fluoropolymer dispersion, wherein the aqueous fluoropolymer dispersion is stabilized by the use of a surfactant that does not substantially remain in an electrode coating film after a drying step during electrode production.

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 invention provides a fluoropolymer liquid composition comprising a fluoropolymer and a film-forming auxiliary, said fluoropolymer comprising acid/acid salt fluorovinyl ether units represented by the general formula (I): said film-forming auxiliary being an organic liquid which is compatible with water and has a boiling point higher than 100° C. but not higher than 300° C., said fluoropolymer liquid composition being a fluoropolymer dispersion composition comprising said film-forming auxiliary and a fluoropolymer fine particle comprising said fluoropolymer, said fluoropolymer fine particle containing, at the proportion of at least 25% by mass thereof, a spherical fluoropolymer fine particle, and said spherical fluoropolymer fine particle being substantially spherical.

Abstract: A fluoropolymer solid composition which contains a fine particle comprising a fluoropolymer, said fluoropolymer having an acid/acid salt group, said acid/acid salt group being a sulfonic acid group, —SO2NR17R18, a carboxyl group, —SO3NR1R2R3R4, —SO3M11/L, —COONR5R6R7R8 or —COOM21/L (in which R17 and R18 are the same or different and each represents a hydrogen atom, an alkali metal, an alkyl group or a sulfonyl-containing group, R1, R2, R3 and R4 are the same or different and each represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, R5, R6, R7 and R8 are the same or different and each represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, M1 and M2 are the same or different and each represents a metal whose valence is L, and said metal whose valence is L is a metal belonging to the group 1, 2, 4, 8, 11, 12 or 13 of the periodic table); said fine particle comprising the fluoropolymer containing, at the proportion of at least 25% by mass thereof, a spherical fluoropolymer

Abstract: An electrode additive comprising an aqueous fluoropolymer dispersion, wherein the aqueous fluoropolymer dispersion is stabilized by the use of a surfactant that does not substantially remain in an electrode coating film after a drying step during electrode production.

Abstract: The present invention provides a process for producing a fluorinated ionomer, comprising copolymerizing, in the presence of a polymerization initiator, (i) a compound represented by Formula (I) (M)1/LOSO2CFY(CF2)mO(CFXCF2O)nCF═CF2  (I)

Abstract: The invention provides a polymer gel electrolyte or a binder for use in lithium secondary batteries which comprises a copolymer having in the molecule both a segmented polymer chain (a) having the function of retaining membrane strength and a segmented polymer chain (b) having the function of holding a nonaqueous electrolyte. Also provided is a lithium secondary battery containing the electrolyte.

Abstract: To provide a binder for secondary battery using non-aqueous electrolyte which is soluble in usual organic solvents, does not swell in a non-aqueous electrolyte and besides enhances battery performance. As the binder, a copolymer comprising 50 to 80% by mole of vinylidene fluoride, 17 to 50% by mole of tetrafluoroethylene and less than 3% by mole of a monomer copolymerizable therewith is used.

Abstract: An acicular fine particulate material which is coated with a compound containing at least one element selected from among elements of Groups III and IV of the Periodic Table in Periods 5 and 6, the acicular fine particulate material being one of (i) an acicular fine particulate material containing iron carbide, (ii) an acicular fine particulate material containing iron carbide, metallic iron and carbon, and (iii) an acicular fine particulate metallic iron containing carbon, is prepared by a promoted reduction reaction while being effectively prevented from sintering and consequently affords magnetic recording media having a high recording density.

Abstract: The present invention provides a process for preparing a magnetic coating composition with use of magnetic particles containing carbon or magnetic particles consisting primarily of an iron carbide, the process being characterized in that the process includes the step of pre-kneading the magnetic particles with an organic solvent.