聚苯并咪唑／改性聚环氧氯丙烷阴离子交换膜的性能

Properties of Anion Exchange Membranes Based on Polybenzimidazole/Modified Polyepichlorohydrin

通过缩聚法制备了含氟聚苯并咪唑(FPBI),以1–甲基咪唑和聚环氧氯丙烷为原料,制备了咪唑盐修饰的聚环氧氯丙烷(Im PECH),并通过溶液浇铸法制备了FPBI/Im PECH复合膜。系统地研究了复合膜中Im PECH含量的不同对复合膜的力学性能、热稳定性、离子电导率、离子交换容量(IEC)、吸水率、溶胀度等性能的影响。研究结果表明,随着Im PECH含量的增加,复合膜的吸水率、溶胀度、IEC、离子电导率逐渐增加,依然能够保持良好的力学性能和热稳定性。FPBI/Im PECH复合膜在80℃下最高电导率达到55.74 m S/cm,并展示了优异的耐碱性,该复合阴离子交换膜有望在碱性阴离子交换膜燃料电池中得到应用。

Polybenzimidazole (FPBI) was prepared via polycondensation,and imidazolium functionalized polyepichlorohydrin (ImPECH) was obtained from the reaction of 1-methylimidazole and polyepichlorohydrin (PECH). The FPBI/ImPECH composite membranes were prepared by solution casting,and followed by anion exchange with OH–anions. The mechanical property,thermal stability,ionic conductivity,ion exchange capacity (IEC),water uptake and swelling degree of composite membranes were thoroughly studied. The results show that the water uptake,swelling degree and ionic conductivity of FPBI/ImPECH composite membranes increase with increasing the content of ImPECH. The PBI/ImPECH composite membranes show good mechanical property,thermal stability,excellent alkaline stability,and its conductivity up to 55.74 mS/cm at 80℃ . These properties make this type of composite membranes suitable for alkaline anion exchange membrane fuel cells.