PVDF-graft-poly (acrylic acid) (PVDF-g-PAA) was used as the material to prepare UF membrane via the phase inversion method. The solubility parameter of PVDF-g-PAA was tested. The effects of the type of solvents, polymer concentration, additives concentration, as well as the temperature of coagulation bath on the performance and structure of the PVDF-g-PAA membranes were discussed. The results showed that after being grafted with acrylic acid, the solubility parameter of PVDF-g-PAA was increased and the polarity of this polymer was enhanced. When DMF or NMP was used as solvent in the preparation of UF membranes, the membrane had a denser skin layer, a lower water flux and a higher rejection of BSA; when DMSO was used as solvent, there were some larger pores distributed on the membrane surface layer, and the membrane had the highest water flux and the lowest rejection of BSA; with the increase in the polymer concentration, the membrane structure became denser, the water flux decreased and the rejection of BSA increased; the increase in PEG400 concentration would lead to an increase in membrane flux and a more porous surface layer. Moreover, the thickness of the membranes also increased, and the starting position of macrovoids shifted further into the membranes; within the temperature range of 12-23 ℃ , with the increase in temperature, the flux of the membrane increased, and the rejection of BSA decreased.%采用粉体辐射接枝丙烯酸的聚偏氟乙烯( PVDF-g - PAA)为材料,以浸没沉淀相转化法制备PVDF- g- PAA超滤膜,研究了接枝后材料溶解性能的变化、以及溶剂种类、聚合物浓度、添加剂种类及浓度、凝胶浴温度制膜参数对PVDF- g- PAA膜结构及性能的影响.结果表明:辐射接枝丙烯酸后,聚合物的溶度参数增大,同时聚合物的极性也增强.在溶剂影响的考察中,以二甲基甲酰胺(DMF)和N-甲基吡咯烷酮(NMP)为溶剂制备的PVDF-g-PAA膜表面致密,透过通量小,对牛血清蛋白( BSA)截留率高；而以二甲基亚砜(DMSO)为溶剂制备的PVDF - g- PAA膜表面孔径较大,透过通量最大,对BSA截留率迅速下降；聚合物浓度的增加使得PVDF- g- PAA膜结构更加致密,纯水通量降低,截留率增加；随着添加剂PEG400浓度的增加,PVDF-g-PAA膜透过通量增加,膜的皮层多孔性增加,厚度增加,大孔发生的起始点向膜内部迁移；在考察的温度区间内(12～23℃),随着凝胶浴温度的升高,PVDF-g -PAA膜通量变大,截留率降低.
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