改性逆热致相分离法制备亲水性聚醚砜超滤膜及其性能

Preparation and Properties of Hydrophilic Polyethersulfone Ultrafiltration Membrane by Modified RTIPS

通过在非低临界共溶温度三元成膜体系聚醚砜(PES)/N,N-二甲基乙酰胺(DMAc)/一缩二乙二醇(DEG)中添加亲水性超支化聚酯(HBPE)成功构建了四元低临界共溶温度(LCST)成膜体系,采用改性逆热致相分离(m-RTIPS)法一步制备了亲水性PES微孔膜。通过扫描电镜、亲水性、渗透性和力学性能实验研究了LCST体系的构建机理和HBPE添加量对膜结构和性能的影响。结果表明,随着HBPE质量比的增加,铸膜液体系的LCST降低;以m-RTIPS法所制得的膜表面开孔率较高、平均孔径较大且可抑制膜断面指状孔的形成并向双连续结构转变,同时膜的渗透性能和力学性能均优于NIPS法所制膜;膜表面的接触角随HBPE质量比的增加而减小,表面膜的亲水性得到改善,抗污染能力增强。

A novel method was presented to construct a quaternary membrane formation system featured a low critical solution temperature(LCST)by incorporating hydroxy terminated hyperbranched polyester(HBPE)into ternary membrane formation system PES/DMAc/DEG which was a non-LCST system,and hydrophilic polyether sulfone(PES)microporous membranes were prepared via modified reverse thermally induced phase separation(m RTIPS)process.The construction mechanism of LCST system and effect of HBPE content on the structure and properties of PES membranes were studied by morphology,hydrophilicity,permeation performance and mechanical properties.The results show that the cloud point decreases as the HBPE concentration increases.SEM images reveal that there are more pores on the top surface and bigger mean pore size when using m-RTIPS process rather than NIPS.In addition,finger-like pores in the cross-section gradually disappear and transfer to bicontinuous structure.When the membranes were prepared via m-RTIPS,the PES membranes show better permeation properties and mechanical properties than the membranes prepared via NIPS process.Furthermore,the water contact angle decreases with the addition of HBPE,which indicates that the hydrophilicity of membrane surface is improved,and the anti fouling property is also enhanced.