Abstract: A fluoropolymer of a monomer (I) represented by the general formula (I), wherein a content of a polymerization unit (I) derived from the monomer (I) is 50% by mass or more based on all polymerization units constituting the fluoropolymer: CX2?CX—O—Rf—SO3M??General formula (I) wherein X is independently F or CF3; Rf is a fluorine-containing alkylene group having 1 to 40 carbon atoms or a fluorine-containing alkylene group having 2 to 100 carbon atoms and having an ether bond or a keto group; and M is —H, a metal atom, —NR74, imidazolium optionally having a substituent, pyridinium optionally having a substituent, or phosphonium optionally having a substituent, wherein R7 is H or an organic group. Also disclosed are an aqueous solution and coating composition containing the fluoropolymer.

Abstract: A method for producing a fluoropolymer, which includes polymerizing a monomer (I) represented by the general formula (I) in an aqueous medium to produce the fluoropolymer of the monomer (I), wherein an oxygen concentration in a reaction system of the polymerization is maintained at 500 ppm by volume or less: CX2?CY—CF2—O—Rf-A ??General formula (I): wherein X and Y are independently H, F, CH3, or CF3, and at least one of X and Y is F; Rf is a fluorine-containing alkylene group having 1 to 40 carbon atoms, or a fluorine-containing alkylene group having 2 to 100 carbon atoms and having an ether bond; and A is —COOM, —SO3M, —OSO3M, or —C(CF3)2OM, wherein M is H, a metal atom, NR74, imidazolium optionally having a substituent, pyridinium optionally having a substituent, or phosphonium optionally having a substituent, and R7 is H or an organic group.

Abstract: Provided is a fluoropolymer of a monomer (I) represented by the following general formula (I), wherein a content of a polymerization unit (I) derived from the monomer (I) is 40 mol % or more based on the entirety of polymerization units constituting the fluoropolymer, and the fluoropolymer has a weight average molecular weight (Mw) of 1.4×104 or more: CX2?CX—O—Rf-A??General formula (I) wherein X is independently F or CF3; Rf is a fluorine-containing alkylene group having 1 to 40 carbon atoms or a fluorine-containing alkylene group having 2 to 100 carbon atoms and having an ether bond or a keto group; and A is —COOM, —SO3M, —OSO3M, or —C(CF3)2OM, wherein M is —H, a metal atom, —NR74, imidazolium optionally having a substituent, pyridinium optionally having a substituent, or phosphonium optionally having a substituent, and R7 is H or an organic group.