| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a sulfonic acid functionalized polymer that is useful in manufacturing of a polymer film of an electrolytic cell, such as a fuel cell. <P>SOLUTION: A method is provided for aqueous emulsion copolymerization of two or more fluoromonomers including: (1) a step of forming an aqueous pre-emulsion by mixing a fluoromonomer expressed by formula (I), F<SB POS="POST">2</SB>C=CF-R<SP POS="POST">1</SP>-SO<SB POS="POST">2</SB>X (where, in the formula, R<SP POS="POST">1</SP>represents a branched or unbranched perfluoroalkyl, perfluoroalkoxy, or perfluoroether group including 1 to 15 carbon atoms and 0 to 4 oxygen atoms, and X represents F, Cl, or Br), together with 0.001 to 0.9 molar equivalent of a base in the absence of added emulsifier; and (2) a step of forming a fluoropolymer latex containing a fluoropolymer in which more than 1 mol% of monomer units are derived from the fluoromonomer expressed by formula I, by reacting the pre-emulsion with one or more perfluorinated comonomers in the absence of added emulsifier. <P>COPYRIGHT: (C)2012,JPO&INPIT |
