BLOCK POLYMER, PRODUCTION METHOD FOR POLYMER, AND LIQUID COMPOSITION CONTAINING BLOCK POLYMER

摘要

PROBLEM TO BE SOLVED: To provide a polymer which has a high water content while water- repellent, excellent in oxygen permeability, and useful as a resin for electrodes of solid polymeric fuel cells. SOLUTION: A block copolymer is provided which comprises segments based on a perfluoropolymer having sulfo groups and segments based on a perfluoropolymer substantially having no ion-exchange group and having alicyclic structures in the main chain or segments based on a polymer substantially having no ion-exchange group and containing repeating units derived from a perfluorovinyl ether.