添加剂对聚砜膜气体分离性能和结构的影响

以聚砜为膜材料,通过浸入沉淀相转化法制备聚砜平板膜.溶剂为N,N-二甲基乙酰胺,凝胶介质为水.以有机小分子无水乙醇、正戊醇、丙酮、磷酸三丁酯,有机大分子聚乙二醇(PEG-400,PEG-2000)和无机小分子无水氯化锂为添加剂来调节膜结构,通过渗透性、选择性和电镜图(SEM)来评价添加剂对膜性能、结构的影响,选择工业上适用于气体分离的添加剂.结果表明,聚乙二醇有较高的渗透性和选择性,其次为磷酸三丁酯,但由于聚乙二醇价格昂贵,所以选择磷酸三丁酯为较优添加剂.

Effects of additives on performance and structure of polysulfone membrane for gas separation

Polysulfone flat-sheet membrane was prepared through phase inversion process. The solvent was N,N-dimethyl-acetamide and the coagulant was water. The organic additive of absolute ethyl alcohol,n-amyl alcohol,acetone,tributyl phosphate,polyethylene glycol（ PEG-400,PEG-2000） and the inorganic additive of lithium chloride（ LiCl） were used to control the structure of the membrane. The effect of different additives on the permeation and selectivity were investigated,and the structure of the membrane was detected by scanning electron microscope（ SEM） technique. The results showed that the polysulfone membrane with polyethylene glycol as the additive exhibited good gas-separation performance. But the polyethylene glycol is too expensive,so we select tributyl phosphate as the better additive.