凝固浴组成对聚醚砜/磺化聚砜共混膜结构及性能影响

Effect of coagulation bath composition on structure and performance of PES/SPSf blend membrane

为考察不同凝固浴组成对聚醚砜/磺化聚砜共混膜结构及性能的影响规律,以聚醚砜(PES)、磺化聚砜(SPSf)为膜材料、N,N-二甲基乙酰胺(DMAc)为溶剂、聚乙二醇(PEG)为致孔剂、H_2O为非溶剂添加剂,采用浸没沉淀相转化法制备PES/SPSf共混超滤膜,对所得共混膜进行SEM、纯水通量、BSA截留等性能表征,分析凝固浴组成亦即不同盐种类对PES/SPSf共混膜结构及性能的影响规律.结果表明:在不同凝固浴条件下所得PES/SPSf共混膜均为海绵体结构;当纯水作为凝固浴时,膜的纯水通量最低(920 L/(m^2·h));当在凝固浴中添加盐时,所得膜的皮层厚度明显降低,特别当凝固浴为NaCl饱和溶液时,所得膜的皮层厚度仅为2.5μm,同时具有最低的静态水接触角(64°),纯水通量为1 024 L/(m^2·h).

In order to study the effect of coagulation bath composition on the structure and property of polyethersulfone （PES）/sulfonated polysulfone （SPSf） blend membrane, the PES/SPSf blend membranes were prepared via non-solvent induced phase separation using PES and SPSf as membrane materials, N,N-dimethylacetamide（DMAc） as solvent, PEG as pore for^ning agent and H2O as non-solvent addition. The PES/SPSf blend membrane was characterized by SEM, pure water flux, BSA rejection and so on. The effects of coagulation bath composition on the structure and perfor^mance of membrane were investigated. The results indicated that all the membranes obtained from the coagulation bath with different compositions possessed the sponge -like structure. The pure water flux of the obtained blend membrane was 920 L/（m2 ＊h） when the pure water was employed as the coagulation bath. The thickness of skin layer reduced when a salt solution was added in the coagulation bath. Specially, the thickness of skin layer was 2.5 滋 m and the water contact angle was 6 4 ., and the pure water flux of the obtained blend membrane was up to 1 024 L/（m2,h） when NaCl solution was used as the coagulation bath.