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

摘要: Abstract To develop polymer electrolyte membrane with both high hydroxide conductivity and good alkaline stability, series of poly(arylene ether sulfone)s block copolymers bearing varied imidazolium functionalized aromatic pendants are synthesized, the relationship between ionic properties investigated discussed. Atomic force microscopy (AFM) results suggest that, well-controlled pendent chain structures responsible for formation well-defined microphase-separated morphology which is benefit to construct highly conductive transport channels in membrane. The membranes tethering longer (Im-DFDM-bPES) exhibit large than those shorter ones (Im-DFDB-bPES) spite their comparable IEC values, this accordance sizes hydrophilic domains Among membranes, Im-DFDM-bPES-x7y32 1.30 mequiv g−1 gives highest (34.2 98.7 mS cm−1 at 25 80 °C, respectively). Besides, Im-DFDM-bPES Im-DFDB-bPES stability after aging under severe conditions (4 M NaOH 80 °C) 144 h, where aged give remaining by 74.8%–77.2% 64.5%–66.4%, mechanical maximum stress 47.36–51.30 MPa 60.03–62.28 MPa, respectively, indicating chemical moiety copolymer backbone.