Studies on Analysis of Relationship between Permeation Separation and Membrane Structure for Organic Liquid Mixtures through Polymer Membranes

从膜的化学结构和物理结构出发，研究了苯/环己烷混合物在聚合物膜中的渗透汽化分离特性，并对渗透分离机理进行了探讨。这种渗透选择性与膜的化学和物理结构密切相关。由于混合料对膜的溶胀抑制作用显著提高，因此对壳聚糖和纤维素进行了苯甲酰化处理。这些苯甲酰化壳聚糖膜和纤维素膜对苯有很高的选择性。从亲水性聚合物的化学改性和膜物理结构的构建两个角度，研究了膜结构因素对乙醇水溶液渗透选择性的影响。季铵盐化壳聚糖膜的亲水性和交联度最优，具有较高的水选择性。用PDMS-g-聚氟丙烯酸酯表面修饰的聚[1-(三甲基硅基)-1-丙炔]膜对乙醇水溶液表现出较高的乙醇渗透选择性，而由DMS大单体和甲基丙烯酸烷基酯制备的接枝共聚膜对VOS稀水溶液表现出较高的VOC渗透选择性。接枝共聚物的组成对膜的渗透选择性有显著影响，并与接枝共聚膜微相分离结构的形态密切相关。

Characteristics of permeation and separation for benzene/cyclohexane mixtures in pervaporation through polymer membranes were studied from the viewpoint of chemical and physical structure of the membranes, and mechanism of permeation and separation is also discussed.Liquid crystalline polymer membranes from poly(dimethyl siloxane)(PDMS) with mesogen group and methylmethacrylate-methacrylic acid copolymer membranes cross-linked with metal ions showed benzene-permselectivity. This permselectivity is significantly related to the chemical and physical structure of the membranes. Because depression of swelling of the membrane due to feed mixtures is remarkably improved permselectivity, chitosan and cellulose were benzoylated. These benzoylated chitosan and cellulose membranes were very high benzene-permselective. It made that hydrophilic-hydrophobic balance of the membrane was very important clear.Effect of factor of the membrane structure on the permselectivity for aqueous alcohol solutions was investigated from the viewpoints of chemical modification of hydrophilic polymers and construction of physical structure of the membrane. Optimum in degrees of hydrophilicity and cross-link of quaternized chitosan membranes gave high water-permselective. Poly [1-(trimethylsilyl)-1-propyne] membranes surface-modified with a PDMS-g-poly(fluoroacrylate) showed high ethanol-permselectivity for aqueous ethanol solutions.Graft copolymer membranes prepared from DMS macromonomer and alkylmethacrylates showed high volatile organic compound(VOC)-permselectivity for an aqueous dilute VOS solution. This permselectivity was significantly influenced by composition of graft copolymer, and furthermore was deeply related to morphology in microphase separated structure of the graft copolymer membranes.