Synergistic Effect of Localized Three-Dimensional Polymer Backbone and Self-Assembling Cation for the Construction of Novel Anion Exchange Membrane

In this work, a series of novel anion exchange membranes (AEMs) are constructed using the synergistic action of an alkoxy cationic side chain and a three-dimensional branched monomer. The alkoxy cationic side chain creates fine hydrogen-bonding networks, and the presence of self-assembly effects contributes to ionic clustering within the membrane, resulting in efficient OH– transport. Trip-PTP-O-40 membrane achieves an OH– conductivity of 147.86 mS cm–1 at 80 °C. The selected branched polymer backbone has a localized three-dimensional structure and effectively limits the swelling of the membrane. Even in the presence of hydrophilic hydrogen bonding networks, Trip-PTP-O-40 membrane still maintains a swelling ratio of 15.96% (at 80 °C). The conductivity residual rate of Trip-PTP-O-40 membrane remains 93.7% and 80.1% after 1000 h at 80 °C in a solution of 2 M/5 M NaOH. In the cell testing, the Trip-PTP-O-40 membrane achieves a peak power density of 840.7 mW cm–2. In addition, the polymer backbone prepared by ultrastrong acid catalysis can reach the polymerization end point quickly, which significantly improves the production efficiency. This experiment provides a new idea for the exploitation of high-performance AEMs.