Patent ID: 7488788
Filing Date: 2009-02-10
Classification: C08J,H01B,H01M,Y02E,Y02P

Abstract:
1. An electrolyte polymer for polymer electrolyte fuel cells, made of a perfluorinated polymer having sulfonic groups, characterized in that in a test of immersing 0.1 g of the polymer in 50 g of a fenton reagent solution containing 3% of an aqueous hydrogen peroxide solution and 200 ppm of bivalent iron ions at 40° C. for 16 hours, the amount of eluted fluorine ions detected in the solution is not more than 0.002% of the total amount of fluorine in the polymer immersed, wherein the polymer is made by a process comprising heated a perfluorinated polymer having precursor groups for sulfonic groups, followed by contacting the polymer with fluorine gas, and then followed by converting the precursor groups to sulfonic groups.