Patent ID: 8097383

Claim:
An electrolyte material for polymer electrolyte fuel cells, which is made of a polymer containing repeating units based on a fluoromonomer having a radical polymerization reactivity, wherein the repeating units contain, in their side chains, a structure of the following formula (α) having ionic groups: provided that the symbols in the formula have the following meanings: Each of Q 1 and Q 2 which are independent of each other, is a C 1-6 perfluoroalkylene group which may have an etheric oxygen atom and at least one of perfluoroalkylene groups for Q 1 and Q 2 has an etheric oxygen atom, R f1 is a perfluoroalkyl group which may have an etheric oxygen atom, and X is an oxygen atom, a nitrogen atom or a carbon atom, provided that when X is an oxygen atom, a=0, when X is a nitrogen atom, a=1, and when X is a carbon atom, a=2, and Y is a fluorine atom or a monovalent perfluoro organic group.