聚乙烯醇/改性壳聚糖杂化膜的制备及其碱回收性能

摘要

采用壳聚糖(CS)和1,3-丙磺酸内酯反应生成-SO3H基团并依次加入聚乙烯醇(PVA)和正硅酸四乙酯(TEOS),通过溶胶-凝胶法与磺化CS交联制备一系列具有不同磺化CS含量的新型磺化PVA/CS/SiO2杂化膜.采用傅里叶变换红外光谱、扫描电子显微镜和动态热力学测试技术、以及离子交换容量,含水量、线性膨胀率等数据系统地研究了磺化CS含量对杂化膜的物理和化学性能的影响.结果表明,膜的水含量、线性膨胀率和离子交换容量的范围分别为10 ％～25％、15 ％～20％、0.10～0.65 mmol/g;制备的杂化膜拥有优异的OH-离子渗析性能和可接受的选择性,渗析系数(Uon)和分离因子(S)范围分别为0.013 5～0.016 0 m/h、15.6～26.9.%In this paper,hybrid membranes containing SiO2 particles were prepared by a crosslinking reaction of poly(vinyl alcohol) with sulfonated chitosan in the sol gel process,and the effect of sulfonated chitosan content on the structure and performance of hybrid membranes was investigated by Fourier-transform infrared spectroscopy,scanning electron microscopy,dynamic mechanical analysis,ion-exchange capacity,water uptake and linear expansion.The results indicated that the hybrid membranes presented water-uptake amounts of 10 wt ％～15 wt ％,linear expansion rates of 10 ％ ～ 15 ％ and ion-exchange capacities of 0.10 ～ 0.65 mmol/g.The hybrid membranes prepared exhibited an excellent OH-ion transport property and acceptable selectivity,and their dialysis coefficient and separation factor of alkali recovery were in the range of 0.013 5～0.016 0 m/h and 15.6～26.9,respectively.