Patent ID: 7829209

Claim:
A solid polymer electrolyte for a fuel cell, comprising: a proton conductive resin of Structural Formula 1 having side chains R 1 , R 2 , R 3 and R 4 bonded to an aromatic polyurea resin backbone, wherein each of X 1 and X 2 is selected from the group consisting of S, O, a sulfonyl group, a C 1-3 linear methylene group, a difluoromethylene group, a hexafluoropropylene group, and a hetero aromatic ring, wherein at least one of the side chains R 1 , R 2 , R 3 and R 4 is an alkylsulfonic acid group or a carboxylic acid group, and wherein n is in the range of about 20 to about 1000.