Method for producing solid polymer electrolyte membrane, solid polymer electrolyte membrane, membrane electrode assembly for solid polymer fuel cell, and solid polymer fuel cell

摘要

The invention provides a method for fabricating a reinforced polymer electrolyte membrane having greatly enhanced durability against a dry/wet cycle or freeze/defreeze cycle. In a method for fabricating a reinforced polymer electrolyte membrane according to the present invention, (1) a polymer electrolyte precursor is caused to infiltrate into a sheet-like porous reinforcing member, in the absence of a solvent, at a temperature higher than the melting point of the sheet-like porous reinforcing member, or (2) the polymer electrolyte precursor is first caused to infiltrate into the sheet-like porous reinforcing member, in the absence of a solvent, at a first temperature lower than the melting point of the sheet-like porous reinforcing member, and then heat-treated at a second temperature higher than the melting point of the sheet-like porous reinforcing member; thereafter, the polymer electrolyte precursor is transformed into a polymer electrolyte by hydrolyzing the polymer electrolyte precursor.