摘 要：将凹凸棒石-g-聚氮异丙基丙烯酰胺（PGS-g-PNIPAAM）与聚偏氟乙烯（PVDF）共混制备温敏性混合基质超滤膜，利用凝固浴温度诱导表面偏析增强超滤膜的亲水性改性。结果表明，在5 °C和20 °C下制备的混合基质膜膜面的含N1s量分别为1。77%和1。02%，而40 °C下制备的膜只有0。73%；5 °C和20 °C下制备的PVDF/PGS-g-PNIPAAM混合基质膜的初始水接触角分别为75。2°和75°，比40 °C制备的膜低大约6°；5 °C下制备的混合基质膜在40 °C时的纯水通量高达366 L·m-2·h-1，而40 °C下制备的膜仅达274 L·m-2·h-1，并且低温制备的混合基质膜的最大孔径小，膜厚度低，孔隙率大；过滤BSA溶液时，添加改性剂的PVDF膜渗透通量高，下降速率减慢；综上所述，温度诱导表面偏析增强了混合基质超滤膜的亲水性、渗透性以及抗污染性能。93806
毕业论文关 键 词：共混改性，表面偏析，聚偏氟乙烯，凹凸棒石，聚氮异丙基丙烯酰胺
Abstract: In this study, a thermo-responsive inorganic-organic nanofiber, palygorskite-g-poly(N-isopropylacrylamide) (PGS-g-PNIPAAM), was incorporated into PVDF matrix for hydrophilic modification。 We utilized surface segregation induced by controlled coagulation bath temperature (CBT) to acquire more hydrophilic membrane surface。 Through controlling the CBT, series membranes were fabricated and the hydrophilicity, permeation as well as microstructure were investigated。 The N1s contents of the hybrid ultrafiltration membranes prepared at 5 and 20 °C are 1。77% and 1。02%, respectively while the one of membrane prepared at 40 °C is just 0。73%。These resulted in higher hydrophilicity and permeability as well as thermo-responsiveness for membranes prepared at lower temperatures。 The initial water contact angle of PVDF/palygorskite-g-PNIPAAM hybrid ultrafiltration membrane prepared at 5 and 20 °C is 75。2° and 75°, respectively, which is about 6° lower than the one prepared at 40 °C。 A higher pure water flux (PWF) of about 366 L·m-2·h-1 at 40 °C was obtained for the hybrid membrane prepared at 5 °C while the one prepared at 40 °C only reached 274 L·m-2·h-1。 Meanwhile, membranes prepared at low temperature exhibited fewer macrovoids, lower membrane thickness and larger elongation。 During the filtration of BSA solution, the permeate fluxes of the modified PVDF membranes were much higher and declined more slowly than that of the pristine one。 Overall, the PNIPAAM modified PGS nanofiber is a promising additive for polymer matrix membranes to reduce fouling。
Keywords: blending modification, surface segregation, polyvinylidene fluoride, palygorskite, poly(N-isopropylacrylamide)
目 录
1 引言 4
1。1 PVDF超滤膜的制备 4
1。2 PVDF超滤膜的亲水性改性 6
1。3 智能膜 8
1。4 立题意义和研究内容 8
2 实验部分 9
2。1 实验药品及仪器 9
2。2 温敏性聚偏氟乙烯-凹土棒石混合基质超滤膜的制备 10
2。3 膜的表面红外测试 11
2。4 膜表面XPS测试 11
2。5 膜的渗透性 11
2。6 膜孔径测试 12
2。7 膜的抗污染性能测试 12
3 实验结果与分析 温敏性聚偏氟乙烯凹凸棒石混合基质超滤膜的温度诱导表面偏析:http://www.youerw.com/huaxue/lunwen_201721.html