In this study, we report the synthesis and properties of new anion exchange membranes using m-polybenzimidazole (m-PBI) as polymer backbone attached with quaternary ammonium group and alkene group as side chains. These ionic m-PBIs were crosslinked by thermal thiol-ene reaction. The ion exchange capacity (IEC) values and crosslinking degrees were controlled independently by the amount of attached quaternary ammonium groups and alkene groups, respectively. m-PBI based AEMs with IEC from 1.51 to 2.50 mmol/g exhibit hydroxide conductivity of 14 to 58 mS/cm at 80 °C. With similar IEC values, crosslinked membranes absorb less water but show similar hydroxide conductivity and better dimension stability than uncrosslinked membranes. A crosslinked membrane with an IEC value of 2.46 mmol/g can retain 84% of its pristine hydroxide conductivity after being immersed in 1.0 M sodium hydroxide solution at 60 °C after 720 h. These membranes in hydrated condition also show mechanical robustness with tensile strength of 10.8 to 14.6 MPa. From the high hydroxide conductivity, enhanced alkaline stability and good mechanical properties, crosslinked ionic m-PBIs are promising candidate as anion exchange membranes for fuel cell application.

在这项研究中，我们报告了以m-聚苯并咪唑（m -PBI）为聚合物主链并连接有季铵基团和烯烃基团作为侧链的新型阴离子交换膜的合成和性能。这些离子米-PBIs通过热硫醇-烯反应进行交联。离子交换容量（IEC）值和交联度分别通过所连接的季铵基团和烯烃基团的量独立地控制。米IEC在1.51至2.50 mmol / g的基于PBI的AEM在80°C下的氢氧化物电导率为14至58 mS / cm。与未交联的膜相比，在具有相似的IEC值的情况下，交联膜吸收的水较少，但显示出相似的氢氧化物电导率和更好的尺寸稳定性。IEC值为2.46 mmol / g的交联膜在720小时后浸入60°C的1.0 M氢氧化钠溶液中后，可以保留其84％的原始氢氧化物电导率。这些在水合条件下的膜还显示出机械强度，拉伸强度为10.8至14.6 MPa。从高的氢氧化物电导率，增强的碱稳定性和良好的机械性能来看，交联的离子型m -PBIs有望成为燃料电池应用中的阴离子交换膜。