| 摘要 |
The present invention provides an electrolyte membrane that can maintain its properties even during long-term use in a solid polymer fuel cell. More specifically, the present invention provides an electrolyte membrane that exhibits excellent adhesion to the electrodes in a solid polymer fuel cell. The electrolyte membrane of the present invention is an electrolyte membrane for a solid polymer fuel cell, in which a graft chain containing a cation-exchange group has been added to a polymer substrate comprising an olefin-type polymer or fluoropolymer, wherein the penetration temperature of the electrolyte membrane, as measured by thermomechanical analysis, is no more than 200°C. This electrolyte membrane preferably has a dimensional variation ratio, upon immersion in a 40 weight% aqueous methanol solution, of no more than 40%. The polymer substrate preferably comprises polyvinylidene fluoride. |
