Bisphenol A based carbon-carbon coupled poly(arylene)s from dibenzoyl-dichlorobenzene via Ni(II) catalyzed and condensation polymerization for PEMFC

Abstract

The major challenges experienced by the researchers till now are to synthesis the chemically and mechanically stable proton exchange membranes. However, Ni catalyzed CC coupling polymerization together with condensation reaction assist to get the high molecular weight polymer membranes as well as thermally and chemically stable PEMs. In this study, bisphenol A-based sulfonated poly (arylene)s copolymers (bis A-SPAs) have been successfully synthesized by the carbon-carbon coupling polymerization using Ni (0) catalyst from sulfonated 1,4-dibenzoyl-2,5-dichlorobenzene (SDBDCB) monomer and subsequently condensation reaction with bisphenol A. The (bis A-SPAs) membranes were flexible in nature and attained high molecular weight. The synthesized (bis A-SPAs) membranes exhibited water uptake from 7.42 to 56.4%, ion exchange capacity ranging from 0.73 to 1.67 meq/g, and proton conductivity from 48.8 to 96.4 mS/cm (at 90 °C) with maximum power density of 0.48–0.60 W/cm2. Membrane with high-sulfonated degree (bis A-SPAs-50) showed almost analogous conductivity (96.4 mS/cm) to Nafion® 117 membrane (98.92 mS/cm) at 90 °C and 90% humidity. The synthesized sulfonated polymer membranes displayed well phase separation that increased the proton conductivity. The TGA and Fenton's test results confirmed that the synthesized membranes possessed admirable thermal stability and mechanical stability. Therefore, the new synthesized (bis A-SPAs) membranes have the promising suitable properties as a proton exchange membrane in the fuel cell applications.