| 摘要 |
PROBLEM TO BE SOLVED: To provide a solid polymer electrolyte fuel cell having high strength even if the membrane is thin, and capable of maintaining high performance for a long time, by using a cation exchange membrane comprising per- fluorocarbon copolymer containing a sulfonic acid group as a solid high polymer electrolyte, including a reinforcement material of polyethylene fiber having a weight average molecular weight of not less than a specific value. SOLUTION: A woven cloth having 10-200 warps and 10-200 wefts/inch independently for each and a thickness of 10-80 μm is obtained by using polyethylene fabric with ultrahigh molecular weight and high density having weight average molecular weight of not less than 1 million, and the number of deniers of 0.8-50. After a gamma ray is radiated to a woven cloth flattened by applying pressure to this woven cloth, an operation to impregnate it in a solution of per-fluorocarbon copolymer containing a sulfonic acid group with concentration of 8% and dry it is repeated. A cation exchange membrane reinforced by this woven cloth consequently obtained has high tensile strength of 8.5 kg/cm and a low specific resistance of 5 Ω.cm and is used for a solid polymer electrolyte. Thereby, high performance can be maintained for a long time. |
