原位聚合凝胶填充法荷正电PVC中空纤维纳滤膜的制备及其纳滤性能的研究

PERPETRATION AND NANOFILTRATION PROPERTIES OF POSITIVELY CHARGED PVC HOLLOW FIBER NANOFILTRATION MEMBRANE VIA IN-SITU POLYMERIZATION AND GEL-FILLING

以PVC中空纤维超滤膜为支撑层,DMC为荷正电单体,PEGDA为交联单体,通过原位聚合的方法在PVC中空纤维超滤膜的内外表面和膜的孔道内引入和填充的荷正电凝胶共聚物,制备得到了荷正电PVC中空纤维复合纳滤膜。考察了原位聚合反应溶液中单体的浓度对凝胶填充量的影响,进而研究了凝胶填充量对膜的机械性能,渗透性能和截留性质的影响。结果表明,通过对聚合单体浓度的调节可以有效地控制凝胶的填充量。随着凝胶填充量的增加,复合纳滤膜的韧性,膜表面亲水性以及膜对小分子染料刚果红与维多利亚蓝B的截留率都有所上升,而膜的通量有所减小。在聚合溶液单体浓度为5%的条件下制备得到的复合纳滤膜,在0.3 MPa下,其对0.05 g/L的刚果红溶液和0.025 g/L的维多利亚蓝B溶液的通量分别为17 L/(m2·h)和21 L/(m2·h),截留率分别为88.9%和99.7%,且分离性能保持稳定。

ositively charged PVC hollow fiber nanofiltration membranes were prepared by filling positively charged gel copolymers onto internal and external membrane surface and in the channels in the method of in-situ polymerization while using polyvinyl chloride （PVC） hollow fiber ultrafiltration membranes as the supporting membranes, methacryloyloxy ethyl trimethyl ammonium chloride （DMC） as the positively charged monomers, and, polyethylene glycol diacrylate （PEGDA） as the cross-linking monomers. Monomer concentrations in reaction solution were tuned to mediate the filling amount of the eopolymers onto membranes. The effect of the gel filling amount on the mechanical properties, permeability and the rejection performance of the membranes was investigated. The results showed that the gel filling amount could be effectively controlled by adjusting polymerized monomer concentrations. With an increasing of the gel filling amount, the toughness, surface hydrophilicity and rejection ratios to Congo Red and Victoria Blue B of the membranes was increased, and the membrane flux decreased as a result. When the monomer concentration of the in-situ polymerization reaction solution was 5wt%, the flux of the membrane for 0.05 g/L aqueous solutions of Congo Red and 0.025 g/L aqueous solutions of Victoria Blue B were 17 L/（m^2.h） and 21 L/（m^2.h） respectively, the rejection of the membrane for such two aqueous solutions were 88.9% and 99.7% respectively. Besides, the separating property of the membranes remains unchanged and exhibits good stability.