Patent ID: 8039165

Claim:
A proton conductive membrane comprising an ion conductive polymer segment (A) which is polyarylene and an ion nonconductive polymer segment (B), the membrane absorbing water when it is soaked in 90° C. water for 30 minutes of which the quantity of water showing melting temperatures in the range of −30 to 0° C. is 0.1 to 2.0 g based on 1 g of the copolymer, wherein the ion nonconductive polymer segment (B) has a structure in which main chain skeletons of the ion nonconductive polymer segment (B) are covalently bound at aromatic rings thereof through binding groups, and wherein the proton conductive membrane has a morphology in which the ion conductive polymer segment (A) forms a continuous phase, and wherein the proton conductive membrane comprises a block copolymer in which the ion conductive polymer segment (A) and the ion nonconductive polymer segment (B) are covalently bound.