abstract |
A method for preparing poly(2,5-benzimidazole) whereby 3,4-diaminobenzoic acid is polymerized using a dehydrating reagent containing P 2 O 5 and CX 3 SO 3 H where X is H or F. The poly(2,5-benzimidazole) has good proton conductivity and low methanol permeability, and therefore can be used as a polymer electrolyte membrane for a fuel cell. |