预辐射接枝丙烯酰胺改性PVDF粉体及其亲水性滤膜的制备

Hydrophilic microfiltration membranes prepared from acryl amide grafted PVDF powder by γ-rays pre-irradiation

通过γ射线预辐射接枝方法将丙烯酰胺(Acryl amide,AAm)单体接枝到聚偏氟乙烯[Poly(vinylidene fluoride),PVDF]粉体上,通过测定粉体接枝前后氟元素含量的变化来计算接枝率。研究了同一单体浓度下,接枝率随反应时间的变化规律,并将具有不同接枝率的改性粉体溶解在N-甲基吡咯烷酮(N-methyl pyrroli-done,NMP)中,使用聚乙烯吡咯烷酮[Poly(N-vinyl pyrrolidone),PVP]为成孔剂,通过相转化法制备得微滤膜。测试了水在膜表面的接触角、膜在水中的溶胀度,水通量随接枝率的变化规律,以及滤膜的抗污染效果。研究表明,接枝丙烯酰胺改性PVDF粉体制备的微滤膜,较未改性粉体制备的微滤膜亲水性明显改善,纯水通量随接枝率的提高而增大,且由接枝率为13%的PVDF-g-PAM粉体制备的微滤膜,抗牛血清蛋白(Bovine serum albumin,BSA)污染性能优于空白PVDF粉体制备的微滤膜。

Acryl amide （AAm） was grafted onto poly （vinylidene fluoride） （PVDF） powder by a γ-rays pre-irradiation induced graft polymerization technique. The DG values of the PVDF-g-PAM powder were determined by fluorine elemental analysis. Effects of grafting time on DG of PVDF-g-PAM powder at the same monomer concentration were studied. And modified powder was dissolved in NMP and added PVP as pore-forming agent. The microfiltration （MF） membranes were cast using a phase inversion method. The contact angle, degree of swelling, water flux and antifouling properties of those modified MF membranes were investigated. The results indicated that the hydrophilicity of modified MF membranes was improved obviously and the antifouling property of modified MF membranes （DG of 13%） was better than that of the pristine membrane.