Imidazolium functionalized block copolymer anion exchange membrane with enhanced hydroxide conductivity and alkaline stability via tailoring side chains

525In this work, series of poly(arylene ether sulfone)s block copolymers bearing varied imidazolium functionalized pendants are developed with different hydrophobic and hydrophilic blocks. The resulting imidazolium functionalized anion exchange membranes exhibit large σ values of 98.7 mS cm−1 at 80 °C for Im-DFDM-bPES membranes, which is attributed to the well-defined microphase-separated morphology. The results suggest that the membranes with longer imidazolium pendants and larger oligomer blocks is beneficial to achieve a better balance between high σ and good alkaline stability.