Tripartite Cationic Interpenetrating Polymer Network Anion Exchange Membranes for Fuel Cells

Abstract

To facilitate large-scale commercial applications of anion exchange membrane fuel cells, high ionic conductivity and long-term durability of anion exchange membranes (AEMs) are crucial. Herein, poly(styrene-co-4-vinylbenzyl chloride) (PSVBC) without aryl ether linkages was synthesized by the radical bulk polymerization using styrene (St) and 4-vinylbenzyl chloride (VBC) as monomers. Then, using PSVBC as the framework material and secondary anion carrier, and polyquaternium-10 (PQ10) as the main anion carrier, the tripartite cationic full-interpenetrating polymer network (F-IPN QPSVBC-PQ10) AEMs were fabricated by the chemical crosslinking method. Upon preparation, the AEMs with distinctive nano-sized microphase separation can maintain a suitable swelling capability, assuring stable mechanical properties, dimensional stability, alkaline stability, and oxidation resistance, surpassing their semi-interpenetrating polymer network QPSVBC-PQ10 AEM counterpart. Specifically, the ionic conductivity and peak power density of the optimally formulated AEM were 81.89 mS/cm and 119.31 mW/cm2, respectively. Meanwhile, 91.06% of the initial mass and 88.37% of the original ionic conductivity were maintained after successive 10-day oxidation test and 30-day alkali resistance test. In summary, the unique design of tripartite cationic F-IPN QPSVBC-PQ10 AEMs without aryl ether linkages is undoubtedly beneficial to further promote the development of high-performance anion exchange membranes.