| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a polymer electrolyte membrane which has high ion conductivity, which exhibits superior mechanical characteristics and dimensional stability even in a wet state, and which is superior even in joining property of a membrane electrode assembly, and to provide a fuel cell or the like using the polymer electrolyte membrane. <P>SOLUTION: This is the polymer electrolyte membrane containing a sulfonic acid group which has a specific structure and of which the tensile breaking strength under atmosphere of 20°C and 65% relative humidity is 40 MPa or more, and of which the tensile elongation measured in water at 25°C is 200% or less, and preferably the polymer electrolyte membrane containing the sulfonic acid group in which difference between the tensile elongation measured in water at 25°C and the tensile elongation measured under the atmosphere at 20°C and 65% relative humidity is 120% or less. The polymer electrolyte membrane is superior in the joining property of the membrane electrode assembly, and appropriate for the fuel cell. <P>COPYRIGHT: (C)2008,JPO&INPIT |
