Improving proton conductivity of poly(oxyphenylene benzimidazole) membranes with sulfonation and magnetite addition

Flexible membranes of poly(oxyphenylene benzimidazole) (PBIO) polymer with oxygen in the main chain were prepared. Proton conductivity was improved by sulfonation and adding magnetite to the PBIO membrane. A hydrophilic PBIO polymer/polyvinylidene difluoride (PVDF) mixture was used to prepare the membrane. DMF/acetone solvent pair was used to obtain homogeneous solutions of these two polymers. By modifying the PBIO with sulfuric acid, the PBIO...