基于聚乙烯醇/支化聚乙烯亚胺离子交换膜不同烃基对其性能的影响

Effects of Different Hydrocarbyl on Properties of Polyvinyl Alcohol/Branched Polyethyleneimine Anion Exchange Membrane

以聚乙烯醇/支化聚乙烯亚胺(PVA/BPEI)为基体,分别选用多种卤代烃为季铵化试剂制备阴离子交换膜(AEMs),并采用多种测试方法对膜的关键性能进行表征,以及基于分子结构对结果进行分析讨论。结果表明,以3-氯-1-丙醇为季铵化试剂制备所得的AEM于80℃电导率可达79. 03 m S/cm,IEC值为3. 1 meq/g,且该膜由于羟基在膜内形成的氢键作用使其具有优异的热力学性能、尺寸稳定性和化学稳定性;膜内季铵基团随其疏水链长度及结构的不同对AEMs性能的影响也有所差异,引入含有羟基的柔性侧链可在膜内构成氢键网络形成亲疏水结构,是提高膜综合性能的有效途径。

Anion exchange membranes （AEMs） consisting of polyvinyl alcohol/branched polyethyleneimine （PVA/IBPEI） were quaternization with various halogenated hydrocarbons and the key performances were characterized. The results were analyzed based on the molecular structure of AEMs, and it is shown that the AEMs prepared with 3-chloro-l-propanol as quaternization reagent possess the ionic conductivity of 79.03 mS/era at 80 ＂C and theion exchange capacity （IEC） of 3.1 meq/g. Moreover, it has excellent thermodynamic properties, dimensional and chemical stability due to the hydrogen bond formed by hydroxyl which exists in membranes, The results show that the effects on AEMs properties caused by quaternary ammonium groups vary with the hydrophobic chain length and its molecular structure. Therefore, the introduction of hydroxyl-containing side chains can form hydrogen-bonding networks within the membrane to form hydrophilic/hydrophobic structures, which is an effective way to improve the overall performance of the membrane.