Highly Conductive And Dimensionally Stable Anion Exchange Membranes Based On Poly(Dimethoxybenzene-Co-Methyl 4-Formylbenzoate) Ionomers

The chemical stability of anion exchange membranes (AEMs) greatly affects their practical applications in alkaline membrane fuel cells. Here, highly conductive and dimensionally stable AEMs based on a copolymer with a triphenylmethane backbone (without aryl ether linkages) were prepared via Friedel-Crafts polycondensation. The as-prepared AEMs showed a high hydroxide conductivity (124.2 mS cm(-1) at 80 degrees C) and good alkaline stability in 2 M KOH solution at 60 degrees C. Furthermore, the AEMs with high ion exchange capacity (IEC: 2.17 mmol g(-1)) displayed high mechanical properties and good dimensional stability. The single H-2/O-2 fuel cell utilizing the PDMB-Pi-0.7 membrane showed a maximum power density of 212.8 mW cm(-2) at a current density of 425.5 mA cm(-2) at 60 degrees C. This study provides a general synthesis strategy for the preparation of stable AEMs with high hydroxide ion conductivity and good dimensional stability for alkaline membrane fuel cells.