Patent ID: 8232353

Claim:
A process for producing a polymer ion-exchange membrane comprising: irradiating a first surface of a polymer film substrate with an ion beam selected from the group consisting of hydrogen ions, helium ions or high-energy heavy ions at 10 4 ˜10 14 /cm 2 for forming holes in the substrate; then adding to the irradiated film substrate at least one monomer selected from monomers having a sulfonyl halide group CF 2 ═CF(SO 2 X 1 ), CH 2 ═CF(SO 2 X 1 ) and CF 2 ═CF(OCH 2 (CF 2 ) 1-4 SO 2 X 1 ), wherein X 1 is a halide group —F or —Cl; degassing the monomer or monomers; heating the film substrate so that the monomer or monomers are grafted onto the substrate; converting the halide group —X 1 in grafted molecular chains to the sulfonate group —SO 3 M, where M is an alkali metal Na or K; and then converting the sulfonate group to the sulfonic acid group —SO 3 H.