聚乙烯醇/改性壳聚糖复合膜的制备及其性能研究

Synthesis and Property of PVA/MCTS Anion-exchange Membranes

利用2,3-环氧丙基三甲氯化铵对壳聚糖进行阳离子化改性,将改性后的壳聚糖(MCTS)与聚乙烯醇(PVA)共混浇铸成膜,并采用化学交联法成功制备出了PVA/MCTS阴离子交换复合膜。采用交流(AC)阻抗、傅立叶变换红外(FTIR)光谱、扫描电镜(SEM)、热重分析(TGA)、拉伸试验等分析技术考察了膜的离子电导率、分子结构、微观形貌、热稳定性、力学强度和耐碱稳定性等性能。结果表明所制备的膜性能优良,电导率达到1.28×10-3 S/cm,含水率为87%。高温浓碱加速劣化试验表明PVA/MCTS膜具有良好的耐碱化学稳定性。

In this study, the 2-hydroxypropyl trimethyl ammonium chloride group was introduced into chitosan in order to obtain the cationic modified chitosan（MCTS） and then the prepared MCTS was polyblended with PVA by using chemical cross-linking method to obtain the anion-exchange membranes（PVA/MCTS）.. Various properties of the PVA/MCTS membranes such as ionic conductivity, molecular structure, micromorphology, thermal stability, mechanical strength and alkali resistance were tested by using AC-impedance spectroscopy, FTIR spectroscopy, scanning electron microscopy（SEM）, thermal gravity analysis（TG）, and tensile strength technique. The test results showed that the membrane prepared had excellent performance and the OH- conductivity reached 1.28×10^-3 S/cm while water uptake was 87%. In addition, the PVA/ MCTS membranes showed high stability to alkaline under the condition of high temperature and concentration.