Poly(arylene ether sulfone) containing tetra(quaternary ammonium pendant groups) for alkaline anion exchange membrane fuel cells

Abstract

A series of poly(arylene ether sulfone)s containing quaternary ammonium pendant groups is prepared for anion conducting membranes. We synthesize a new monomer that contains four amine groups which are changed to ammonium functional groups. By using the functionalized monomer, it is possible to directly obtain fuctionalized poly(arylene ether sulfone) for anion exchange membranes. This process allows precise control of the amount of quaternary ammonium groups and their locations along the polymer backbone. The product is characterized by ¹H NMR, thermogravimetric analysis, water uptake, ion exchange capacity, conductivity and cell performance. The anion exchange membranes formed from these polymers show conductivities above 40 mS/cm at 30 ℃. In fuel cell test, the maximum power output of 77 mW/cm² is achieved using hydrogen and oxygen.