FILM FOR REINFORCING ELECTROLYTE MEMBRANE OF SOLID POLYMER FUEL CELL

摘要

A biaxially oriented film for reinforcing the electrolyte membrane of a polymer electrolyte fuel cell, wherein the film comprises (i) a layer mainly composed of polyethylene naphthalene dicarboxylate and has (ii) a Young's modulus in at least one direction of not less than 9,000 MPa and (iii) a thickness of 15 to 150 µm. The biaxially oriented film has a satisfactory reinforcing effect as a reinforcing member for a polymer electrolyte membrane at the operation temperature of a polymer electrolyte fuel cell though it is a thin film.