采用相转化法,以聚丙烯腈聚合物为制膜材料,研究了聚合物的浓度、凝胶浴温度、挥发时间及各种添加剂对膜结构和性能的影响。采用扫描电子显微镜、凝胶渗透色谱等手段对底膜进行了表征。结果表明:采用增加聚合物的浓度、降低凝胶浴温度或加长挥发时间,以及在一定范围内增加添加剂H2O、ZnCl2和正丁醇含量等方法,都可以明显改变膜性能,使膜断面由大空腔结构趋向海绵孔结构。制备了具有海绵孔断面结构的,用作气体分离复合膜底膜的PAN超滤膜。
In this study, Polyacrylonitrile (PAN) was used to prepare the substrate membrane with sponge-like cross section for gas separation composite membrane. The influences of polymer concentration, temperature of coagulation bath, evaporation time and introduction of additives on membrane performance were investigated by Scanning Electron Microscopy and Gel Permeation Chromatography. It indicated that increasing polymer concentration, evaporation time, amount of additives (H2O, ZnCl2 and 1-Butanol) and decreasing temperature of coagulation bath, were all effective methods to regulate the membrane performance and obtain the membrane with sponge-like structure.