| abstract |
Ion-Exchange polymers for a polymer electrolyte membrane include a moiety of formula (I), and/or a moiety of formula (II), and/or a moiety of formula (III) wherein at least some of the units I, II and/or III are sulphonated. The phenyl moieties in units I, II, and III are independently optionally substituted and optionally cross-linked; m, r; s, t, v, w and z independently represent zero or a positive integer, E and E' independently represent an oxygen or a sulphur atom or a direct link, G represents an oxygen or sulphur atom, a direct link or a -O-Ph-O- moiety where Ph represents a phenyl group and Ar is selected from one of the moieties (i) to (x) as set forth herein which is bonded via one or more of its phenyl moieties to adjacent moieties. |