Formation of Poroas Membrane by Phase soparation with Supercritica/CO_2

Supercritica/CO_2相分离形成Poroas膜

基本信息

批准号：
11450299
负责人：
TERAMOTO Masaaki
金额：
$ 4.16万
依托单位：
Kyoto Institute of Technology
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B).
财政年份：
1999
资助国家：
日本
起止时间：
1999 至 2000
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-11450299/
关键词：
sapercritica CO_2 phase Separation Microporous Membrane Polystyrene Cellulose Acetate 光散乱法 spinodal分解

项目摘要

Microporous polystyrene membranes were prepared by the phase separation process using the supercritical CO_2 as a nonsolvent for the polymer solution. The thin polymer solution in a laboratory dish was located inside a cell and the supercritical CO_2 was introduced to induce the phase separation. The dry flat microporous membranes were obtained without collapse of the structure after the CO_2 pressure was diminished. Effects of the experimental conditions such as the CO_2 pressure, the polymer concentration and the temperature on the average pore size and membrane porosity were investigated.In the preparation of porous cellulose acetate membrane by phase separation with supercritical CO_2, five kinds of diluents were used and effect of the diluent on the membrane structure and performance was investigated. As the mutual affinity between diluent and supercritical CO_2 decreased, the membrane porosity and the average pore size near the center position increased and the thicker skin layer was formed at the top surface. In all cases, macrovoid was not formed, although the phase separation occurred instantaneously after CO_2 was introduced. This was a contrast to the macrovoid formation in the condition of instantaneous phase separation using water as nonsolvent. The membrane performances such as the solute rejection coefficient and the water permeability were measured for the obtained porous membranes.

通过使用超临界CO_2作为聚合物溶液的非危机，通过相分离过程制备微孔聚苯乙烯膜。实验室碟中的薄聚合物溶液位于细胞内，并引入了超临界CO_2以诱导相分离。在CO_2压力降低后，可获得干燥的平坦微孔膜而没有结构崩溃。研究了实验条件（例如CO_2压力，聚合物浓度和温度）对平均孔径和膜孔隙率的影响。在用超临界CO_2的相位分离中，使用了五种稀释剂来制备乙酸多孔纤维素乙酸膜，并研究了五种稀释剂，并研究了稀释剂对膜结构和性能的影响。随着稀释剂和超临界CO_2之间的相互亲和力减少，膜孔隙度和中心位置附近的平均孔径增加，并在顶部表面形成较厚的皮肤层。在所有情况下，均不形成大型，尽管在引入CO_2后立即发生相分离。这与使用水作为非电气化的瞬时相分离的条件与大型形成形成鲜明对比。测量获得的多孔膜的膜性能，例如溶质排斥系数和水的渗透率。