丙烯腈-顺丁烯二酸酐聚合物亲水改性聚苯砜膜

Hydrophilic Modification of PPSU Membranes Using PANCMA Polymers

通过非溶剂诱导相分离的方法制备聚苯砜(PPSU)膜,首先通过水相聚合法制备丙烯腈顺丁烯二酸酐(PANCMA)聚合物,分别通过红外光谱(FT-IR)和X射线衍射(XRD)表征此聚合物,由于此聚合物中存在大量羧基官能团,所以采用该聚合物亲水改性PPSU膜,考察了不同含量PANCMA聚合物(0%,0.5%,1%,2%,3%(wt))对PPSU膜性能的影响,分别考察了PANCMA聚合物对PPSU膜的微观结构、亲水性、通量、截留分子量、BSA静态吸附量以及对甲基蓝染料截留率的影响,结果表明:通过扫描电子显微镜(SEM)观察膜的微观结构,随着PANCMA聚合物含量的增大,指状孔逐渐减小,并且膜的厚度逐渐增加,随着PANCMA聚合物含量的增加,PPSU/PANCMA复合膜的纯水通量由原膜的59.3 L?m-2?h-1降至10.8 L?m-2?h-1,截留分子量由原膜的17,500 Da降低至4,400 Da,接触角由原来的78°降至38°,PANCMA聚合物一定程度提高了PPSU膜的亲水性,其中以PANCMA聚合物含量为2%(wt)时效果最佳,BSA的静态吸附量与原膜相比降低了近20倍,耐污染性能变好;采用制备的膜过滤甲基蓝溶液,截留率由原膜的54%增至89%,表明改性后膜的截留性能变好。

Polypropylene sulfone （PPSU） films were prepared by non-solvent-induced phase separation. Acrylonitrile maleic anhydride （PANCMA） polymers were first prepared by aqueous phase polymerization, which were characterized by FT-IR and X-ray diffraction （XRD）. PANCMA （0%, 0.5%, 1%, 2%, 3%（wt）） were used to modify PPSU films using its carboxyl functional groups. Effects of PANCMA on microstructure, hydrophilicity, flux, molecular weight cut off, BSA static adsorption capacity and retention rate of methyl blue dye of the film were investigated. SEM results show that with the increase of PANCMA content, finger like structure gradually decreases and the thickness of the film increases. Moreover, pure water flux of the PPSU/PANCMA composite membrane decrease from 59.3 L.rn-Z.h-1 to 10.8 L.m-a.h-1, and the molecular weight cut off decreases from 17,500 Da to 4,400 Da. The contact angle of the film decreases from 78° to 38°. PANCMA improves hydrophilicity of PPSU films and the best performance is found when PANCMA content is 2%（wt）. BSA static adsorption capacity is nearly 20 times lower than that of the original membrane and pollution resistance is improved. The prepared membrane is used to treat methyl blue solution, and the rejection rate increases from 54% to 89%, which indicates that the rejection performance of the modified membrane is improved.