聚氯乙烯-聚丙烯酸嵌段共聚物改性的pH响应性聚氯乙烯超滤膜

发布时间：2018-10-05 14:58

【摘要】：为了改进聚氯乙烯(PVC)超滤膜的渗透和抗生物污染特性,采用单电子转移-蜕化转移活性自由基聚合制备了聚丙烯酸-b-聚氯乙烯-b-聚丙烯酸三嵌段共聚物(PAA-b-PVC-b-PAA),并采用非溶剂诱导相转移法制备了PAA-b-PVC-b-PAA改性的PVC超滤膜。发现PAA-b-PVC-b-PAA具有微相分离特性,对应PVC和PAA嵌段的玻璃化温度分别为80和108oC。PAA-b-PVC-b-PAA的引入使膜的指状结构增大。由于PAA-b-PVC-b-PAA共聚物在膜表面的富集,共混物超滤膜的水通量随着PAA链长的增长而增大。随着pH值变化,PAA链段的荷电性和构象变化,使共混物超滤膜的渗透行为具有可逆pH响应性,pH值由2.3增大到11.6时,水通量明显下降;在强酸性和碱性条件下,PAA链段与牛血清蛋白存在强的电荷排斥作用,通量和抗污染性较好。
[Abstract]:In order to improve the percolation and anti-pollution characteristics of PVC (PVC) ultrafiltration membrane, Polyacrylic acid-polyvinyl chloride (PAA-b-PVC-b-PAA) triblock copolymers (PAA-b-PVC-b-PAA) were prepared by single electron transfer and degenerate transfer radical polymerization. PAA-b-PVC-b-PAA modified PVC ultrafiltration membranes were prepared by non-solvent induced phase transfer method. It is found that PAA-b-PVC-b-PAA has the characteristics of microphase separation, and the glass transition temperature of PVC and PAA block is 80 and 108oC.PAA-b-PVC-b-PAA, respectively, which makes the finger structure of the membrane increase. Because of the enrichment of PAA-b-PVC-b-PAA copolymers on the membrane surface, the water flux of the blend ultrafiltration membrane increases with the increase of PAA chain length. With the change of pH value and the charge and conformation of PAA segment, the permeation behavior of the blend ultrafiltration membrane has reversible pH response and the pH value increases from 2.3 to 11.6, and the water flux decreases obviously. Under the condition of strong acidity and alkalinity, PAA segment had strong charge repellent effect with bovine serum protein, and the flux and pollution resistance were better.
【作者单位】：化学工程联合国家重点实验室(浙江大学)浙江大学化学工程与生物工程学院;
【基金】：国家自然科学基金(21676235)
【分类号】：TQ051.893

【相似文献】