基于NIPS法聚苯砜超滤膜海绵孔结构的微观调控

The study of adjusting sponge-like structures on PPSU membrane based on NIPS

以聚苯砜(PPSU)为膜材料,N-甲基吡咯烷酮(NMP)为溶剂,采用NIPS法制备了高通量全海绵孔结构的PPSU超滤膜,对膜微观结构、纯水通量、亲水性、孔隙率及孔径进行了表征,考察了添加剂和凝胶浴组成对膜微观结构和性能的影响.结果表明,在双组分凝胶浴(70%NMP-30%H2O,质量分数)下,PEG1000和PVP的加入使指状孔结构增多,膜通量从29.64 L/(m^2·h)上升到317.50 L/(m^2·h),同时可改善膜亲水性,接触角从76.30°降到65.82°.在三组分凝胶浴(质量分数70%NMP-乙醇-H2O)下,乙醇的加入可促进海绵孔结构的形成,膜通量从139.43 L/(m^2·h)降到49.30 L/(m^2·h),乙醇质量分数为4%时,得到全海绵孔结构的PPSU膜,此时膜通量为70.46 L/(m^2·h).

Polyphenylsulfone(PPSU)ultrafiltration membranes were prepared by non-solvent-induced phase separation(NIPS)method.The effects of different coagulation bath composition and additive composition on the performance of PPSU membranes were investigated.PPSU ultrafiltration membranes were characterized in terms of scanning electron microscopy(SEM),pure water flux,porosity,pore size and contact angle.The results demonstrated that the addition of PEG and PVP lead to the formation of finger-like structure and improve the membrane hydrophilicity at composition of 70%NMP-30%H2O in coagulation bath,which increase the pure water flux increase from 29.64 L/(m^2·h)to 317.50 L/(m^2·h)and contact decrease from 76.30°to 65.82°.Increasing the concentration of ethanol in the coagulation bath can facilitate the formation of sponge-like pores and decrease flux from 139.43 L/(m^2·h)to 49.30 L/(m^2·h).PPSU membrane with full sponge-like structures was obtained at 4%ethanol and the flux is 70.46 L/(m^2·h).