Poly(styrene-<i>b</i>(ethylene-<i>co</i>-butylene)-<i>b</i>-styrene) Cross-Linked Anion Exchange Membranes Grafted with Caged Double Cations and Poly(<i>m</i>-triphenylene-piperidine)
Fanghui Wang, Defang Kong, Shuhuan Zhang, Hong Zhu
Abstract
In order to solve the problems of high swelling rate and poor mechanical properties caused by excessive water uptake of poly(styrene- b -(ethylene-co butene)- b -styrene) (SEBS)-based anion exchange membranes (AEMs), a series of SEBS-C6-MDA-TPIP x membranes with a controllable cross-linking degree were prepared by cross-linking poly( m -triphenylene piperidinium) (TPIP) with SEBS grafted with 1-methyl-1,4-diazabicyclo [2.2.2] octane-1-ammonium iodide. The results showed that with the increase of TPIP content, the swelling of SEBS-C6-MDA-TPIP x membranes decreased, the chemical stability and mechanical properties increased remarkably, and all membranes possessed obvious hydrophilic/hydrophobic microphase separation structures. Among them, the SEBS-C6-MDA-TPIP15% membrane has excellent mechanical properties and high ionic conductivity (86.76 mS cm –1 at 80 °C), and the ionic conductivity only decreased by 20.81% after soaking in a 2 M NaOH solution at 80 °C for 2200 h. H 2 /O 2 fuel cells assembled from the SEBS-C6-MDA-TPIP15% membrane have a maximized power density of 221 mW cm –2 at 80 °C.