Fluorosulfonyl group-containing monomer and its polymer, and sulfonic acid group-containing polymer
A fluorosulfonyl group-containing monomer having a high polymerization reactivity and plural fluorosulfonyl groups, a fluorosulfonyl group-containing polymer and a sulfonic acid group-containing polymer, obtained by using the monomer.
1. A sulfonic acid group-containing polymer comprising one or more units of tetrafluoroethylene and at least one type of units represented by the following formula (5U):
wherein each of R f1 and R f2 which are independent of each other, is a C 1-8 perfluoroalkylene group which may have an etheric oxygen atom between carbon atoms.
2. The sulfonic acid group-containing polymer according to claim 1 , which has a molecular weight of from 5×10 3 to 5 ×10 6 , and contains from 0.1 to 99.9 mol% of units represented by the formula (5U).
3. An electrolyte material for polymer electrolyte fuel cells, which to claim 1 , s the sulfonic acid group-containing polymer according to claim 1 .