Patent ID: 7534515

Claim:
An acid-base proton conducting polymer blend membrane, comprising: a first polymer having acidic subunits; and a second polymer having basic subunits; wherein at least one of said first and second polymers further comprises at least one functional unit selected from the group consisting of hydrophilic units, methanol blocking units, dimension stabilizer units and flexible units, wherein said hydrophilic unit is selected from the group consisting of polyvinylpyrrolidone, poly(n-isopropylacrylamide), poly(2-hydroxy-ethyl methacrylates), copolymers of (vinylpyrrolidone-vinylimidazole), copolymers of (vinylpyrrolidone-dimethylaminoethyl methacrylate), copolymers of (vinylpyrrolidone-stryene), copolymers of (vinylpyrrolidone-vinylacetate), copolymers of (vinylpyrrolidone-vinylacetate-vinyl alcohol), and copolymers of (acrylonitrile-isopropylacrylamide) wherein said methanol blocking units is selected from the group consisting of copolymers of (vinylpyrrolidone-vinylacetate), copolymers of (vinylpyrrolidone-vinylacetate-vinyl alcohol), polyvinylalcohol, polyvinylacetate, copolymers of vinylacetate-vinylalcohol, copolymers of ethylene-vinylacetate, copolymers of vinylpyridine-vinylacetate, copolymers of vinylpyridine-vinylalcohol, and copolymers of vinylpyridine-vinylacetate-vinylalcohol wherein said dimension stabilizer unit comprises a polymer or copolymer comprising a hydrophobic unit selected from the group consisting of polystyrene, polysiloxane, and polyvinyldine fluoride, and wherein said flexible unit comprises vinylidene fluoride copolymer.