CROSSLINKED AROMATIC POLYMER ELECTROLYTE MEMBRANE AND ITS MANUFACTURING METHOD

PROBLEM TO BE SOLVED: To provide a crosslinked aromatic polymer electrolyte membrane that has a low water content and exhibits high proton conductivity, low methanol permeability, a high antioxidative property and excellent mechanical properties, and its manufacturing method. SOLUTION: An aromatic polymer film substrate or a grafted aromatic polymer film substrate having a monomer introduced thereinto as a graft chain is given a crosslinked structure by ionizing radiation irradiation. As the aromatic polymer film substrate and the grafted aromatic polymer film substrate endowed with the crosslinked structure are insoluble in a sulfonating solution, these film substrates are directly sulfonated to give the crosslinked aromatic polymer electrolyte membrane. As introduction of the monomer as the graft chain permits control of the crosslinked structure of the electrolyte membrane and of the microphase separation structure in a proton conductive domain, the crosslinked aromatic polymer electrolyte membrane, which has a low water content and exhibits high proton conductivity, low methanol permeability, a high antioxidative property and excellent mechanical properties, can be prepared. COPYRIGHT: (C)2008,JPO&INPIT