Patent ID: 7547756

Claim:
A polymer composition comprising a sulfonated polyethersulfone and at least one inorganic heteropolyacid, said polyethersulfone comprising structural units derived from at least one biphenol monomer and a monomer of formula I wherein X is O, S or NR 1 ; Y is N or CR 5 , R 1 , R 2 , R 3 and R 4 are independently hydrogen, alkyl, substituted alkyl, aryl, substituted aryl, alkylaryl, substituted alkylaryl, arylalkyl or substituted arylalkyl, or R 3 and R 4 , taken together, form a 5- or 6-membered substituted or unsubstituted aliphatic or aromatic ring; R 5 is hydrogen, alkyl, substituted alkyl, aryl, substituted aryl, alkylaryl, substituted alkylaryl, arylalkyl or substituted arylalkyl; and L is a direct bond or a divalent aromatic linker containing 6-12 carbons.