聚丙烯接枝聚丙烯酸微滤膜的pH响应性

研究了聚丙烯接枝聚丙烯酸微滤膜的pH响应性及其在牛血清蛋白溶液过滤中的抗污染性。聚丙烯酸(PAA)接枝链可提高膜亲水性,但会造成膜孔堵塞:在低接枝率(<17%)下,PAA大幅度提高膜亲水性,膜通量和pH响应性随接枝率的增加逐渐增大;接枝率过大(>17%)时,PAA对膜孔的堵塞作用占主导,膜通量和pH响应性逐渐下降。与未接枝膜相比,在碱性条件下接枝膜对牛血清蛋白(BSA)分子具有一定的抗污染性能,而酸性条件下则加剧BSA对膜的污染,但改性后接枝膜的通量大幅度增长,使这种膜在BSA类蛋白质的微滤领域仍有较好的应用前景。

The pH Sensitivity of Poly (Acrylic Acid )-Graft-Polypropylene Microfiltration Membrane

The pH sensitivity and the antifouling behavior of poly(acrylic acid)-graft-polypropylene microfiltration membranes were investigated by microfiltration experiments.The hydrophilicity of membrane surface was improved by poly(acrylic acid) chains,but membrane pores were blocked at the same time.As grafting degree(dg) is low(<17%),the effect of improving hydrophilicity is dominating so that flux and pH sensitivity are improved with the rise of dg.As dg>17%,both of flux and pH sensitivity decline.During the microfiltration of BSA solution,the grafted membrane show a certain antifouling behavior compared to ungrafted membrane at pH 8;oppositely,in acid condition the grafted membrane show more serious fouling behavior.However,due to the great increase in flux of grafted membranes,grafted membranes still show potential application in protein solution microfiltration technology.