壳聚糖-聚磷酸钠聚离子复合物渗透汽化膜的研究 (Ⅰ)聚离子复合物膜的制备及特性表征

Studies on the pervaporation behaviors of chitosan/sodium polyphosphate polyionic complex membranes (Ⅰ) Preparation and characterization of chitosan/sodium polyphosphate membrane

用长链聚阳离子电解质壳聚糖和短链聚阴离子聚磷酸钠为膜材料 ,采用聚离子复合反应的方法制备出一种新型渗透汽化透水膜———壳聚糖 -聚磷酸钠聚离子复合物膜 .用红外光谱对膜的化学结构进行了分析 ,证实壳聚糖和聚磷酸钠确实发生了聚离子复合反应 ,形成了壳聚糖长链分子与聚磷酸钠短链分子相互缠结的网状结构 .以乙醇 -水体系为研究对象 ,考察了组分在膜内的溶解度和溶解分配关系随体系中乙醇浓度变化的关系 ,这种溶解过程的热力学分配关系直接支配着膜的渗透汽化分离性能 .

A new pervaporation PIC membrane CS-SPP was prepared by interfacial reaction of two oppositely charged polyions,chitosan(CS)and sodium polyphosphate(SPP).The mechanism of polyion reaction was assumed and verified by the results of IR spectral analysis and water-resistant experiments of PIC membranes.The results also confirm that after polyion reaction a kind of crosslinking reticular structure was shaped in membrane.The pervaporation transport process of water-ethanol solution was studied on PIC membrane.The phenomena that swelling degree and permeate concentration changed with feed concentration were observed.This thermodynamic swelling distribution relationship directly controlled the separation proprieties of membrane.