温敏性PVDF/PGS-g-PNIPAM纳米复合超滤膜的制备和性能  

Preparation and properties of temperature-responsive PVDF/PGS-g-PNIPAM nanocomposite ultrafiltration membrane

作　　者：薛爱莲[1] 周守勇[1] 蔡健健 李梅生[1] 张艳[1] 赵宜江[1] XUE Ailian;ZHOU Shouyong;CAI Jianjian;LI Meisheng;ZHANG Yan;ZHAO Yijiang(Jiangsu Engineering Laboratory for Environment Functional Materials,Jiangsu Key Laboratory for Chemistry of Low-Dimensional Materials,School of Chemistry and Chemical Engineering,Huaiyin Normal University,Huai’an 223300,Jiangsu,China)

机构地区：[1]淮阴师范学院化学化工学院,江苏省环境功能材料工程实验室,江苏省低维材料化学重点实验室,江苏淮安223300

出　　处：《化工学报》2020年第3期1380-1389,共10页CIESC Journal

基　　金：国家自然科学基金项目(21476094);江苏省高校“青蓝工程”项目;江苏省“六大人才高峰”高层次人才项目。

摘　　要：通过化学接枝法将聚(N-异丙基丙烯酰胺)(PNIPAM)接枝聚合在凹凸棒石(PGS)纳米纤维表面,制备了系列接枝率的温敏性PGS-g-PNIPAM纳米颗粒,将其与聚偏氟乙烯(PVDF)共混制备温敏性纳米复合超滤膜,深入研究PNIPAM接枝率对膜结构和性能的影响。结果表明,凹凸棒石表面PNIPAM接枝率随溶液中NIPAM单体浓度增大而增加;PGS-g-PNIPAM使复合膜中PVDF晶核变小,数目增多,膜更为疏松多孔,PVDF/PGS-g-PNIPAM膜的平均孔径在20 nm左右,膜的平均孔径和最大孔径均随凹凸棒石表面PNIPAM接枝率的增加而增大;PVDF/PGS-g-PNIPAM膜具有温敏性,温敏开关系数随PNIPAM接枝率的增加先增强后减弱,当接枝率为21.33%时膜温敏开关系数最大,达到1.51,膜渗透通量也最大,对牛血清白蛋白具有良好的截留和抗污染性能。Poly(vinylidene fluoride)(PVDF) has been considered as one of promising membrane materials due to itsexcellent properties such as high mechanical strength, chemical stability etc. and it is widely applied in thepreparation of microfiltration and ultrafiltration membranes. Unfortunately, its hydrophobic nature is susceptible tofouling and remove the foulants with frequently cleaning process may pose irreversible damage to the membranesresulting in reduced membrane lifetime. Therefore, to improve the hydrophilicity and anti-fouling property, athermo-responsive inorganic-organic nanofiber additive(palygorskite-g-poly(N-isopropylacrylamide), PGS-g-PNIPAM) was first fabricated via "graft from" technic and then was incorporated into PVDF matrix.3-Methacryloxypropyl trimethoxy silane(MPS) was used for introducing ethylene groups onto the PGS surface. Aseries of thermo-responsive PGS-g-PNIPAM, with a wide range of grafting yields, were prepared by grafting poly(N-isopropylacrylamide)(PNIPAM) onto PGS-MPS surfaces with the free radical graft polymerization. A series ofcharacterizations including XPS, SEM and TG were conducted and the results indicate that PNIPAM weresuccessfully grafted onto PGS surface and the composite nanofiber owns thermo-responsiveness;the graft ratiogradually reached saturated state as the NIPAM amount increased. The PVDF/PGS-g-PNIPAM hybrid membraneswere prepared via a combination of immersion precipitation(IP) and thermally induced phase separation(TIPS)process. PGS-g-PNIPAM was incorporated into PVDF matrix and the influence of graft ratio, on membranestructures and properties was investigated in detail. The results show that the thermo-responsiveness of membranesascended firstly and then descended lastly as the graft ratio increased and reached the maxium value at the graftratio of 21.33% for the PGS-g-PNIPAM. The PGS-g-PNIPAM nanofibers, which uniformly dispersed in the PVDFmatrix, acted as nucleating seeds and expedited the crystallization process of PVDF. As the increasing graft ratio ofthe P

关 键 词：膜 超滤 聚偏氟乙烯 纳米凹凸棒石 渗透 

分 类 号：TQ028.8[化学工程]