Synthesis and properties of conjugated polyphenylene proton exchange membrane via nickel catalyzed carbon-carbon coupling polymerization

摘要

The synthesis of conjugated polyphenylenes containing tetraphenylethylene (PPTPE) moiety, their functionalization with sulfonic acid groups, and the measurement of apposite parameters for PEMs are described. The polymers were prepared by Ni-catalyzed carbon-carbon coupling reaction of dichlorotetraphenylethylene and 2,5-dichlorobenzophenone. These polymers have all carbon-carbon linkages without any ether linkage on polymer backbone, which were not attacked by nucleophiles (H2O, hydrogen peroxide, hydroxide anion and radical), and the twisted structure provided good solubility in aprotic polar solvent. The sulfonic acid groups were introduced by sulfonation reaction with concentrated sulfuric acid. All these membranes were prepared from dimethylacetamide (DMAc) polymer solution. The membranes were studied by ion exchange capacity (IEC), water uptake, proton conductivity, and single cell performance. The chemical degradation test of the prepared membrane was performed by Fenton reagent, and compared with normal sulfonated poly(ether sulfone)s & Nafion.