Development of composite membrane of crystalline polymers

对聚2-乙烯基吡啶晶体的生长机理进行了探讨，这是制备复合膜的重要特征之一。通过使用正醇和烃的各种组合作为混合溶剂来检查沉淀行为。在正辛醇和十氢萘的混合溶液中，考察了0.03%P2VP溶液中正辛醇浓度对聚合物溶液混浊温度的影响。溶剂中正辛醇浓度越高，混浊温度越高。用其它醇烃混合物作结晶溶剂时，其混浊温度与溶剂中醇浓度的关系相同。结果表明，聚合物浓度降低，混浊温度降低。聚合物浓度与混浊温度之间的关系表明该体系具有低临界溶解温度（LCST）行为。这一关系也表明，该相分离不是液-液相分离，而是固-液相分离。这种固-液相分离对应于溶液生长晶体的形貌不是球形而是片状的事实。界面的扰动是制备两种结晶聚合物复合膜所要解决的问题，

One of the important feature of preparing the composite film, growth mechanism of poly(2-vinyl pyridine) crystal was eluscidated. Precipitation behavior was examined by using various combinations of n-alcohols and hydrocarbons as the mixed solvent. The clouding temperature of polymer solution was examinedas a function of concentration of 1-octanol in the 0.03% P2VP solution in the mixture of 1-octanol and decalin. In higher concentration of 1-octanol in the solvent clouding temperature became higher. Measurement using other combination of alcohol and hydrocarbon for crystallizing solvents resulted in same relationship between clouding temperature and alcohol concentration in the solvent. The results show that the polymer concentration become lower, clouding temperature decrease. This relationship between polymer concentration and clouding temperature indicated that this system showed lower critical solution temperature (LCST) behavior. And this relationship also indicated that this phase separation was not liquid-liquid phase separation but solid-liquid phase separation. This solid-liquid phase separation corresponds to the fact that the morphology of the solution-grown crystal was not spherical shape but platelet. Disturbance of the interface is left for the problem to be solved for preparation of the composite film of two crystalline polymers,