在内外凝胶浴中添加不同含量的溶剂，采用双凝固浴法制备了PVDF/PVP/DMAc中空纤维膜。通过膜形貌扫描电镜（SEM）表征，纯水水通量和BSA截留率测试实验，分析评价了凝固浴中溶剂含量对PVDF中空纤维膜结构与性能的影响。结果表明，凝固浴中溶剂含量增大会导致皮层孔隙率增多，而对亚层结构的影响各不相同。膜的纯水渗透通量变化无明显规律性，但BSA截留率保持相对稳定。当内外凝固浴中溶剂体积分数分别为30%和70%时，膜内部大孔发育良好，亚层疏松多孔，水通量分别为270•m-2•h-1和548L•m-2•h-1，显示了良好的渗透性能。

Polyvinylidene Fluoride (PVDF)/ polyvinylpyrrolidone (PVP) / N,N-dimethylacetamide (DMAc) solutions composite hollow fiber membrane were fabricated by the dual-bath coagulation method, using different content of DMAc / water solution as the first and internal coagulation bath. This study investigated the effect of solvent compositions of coagulation baths on the performance and microstructure of PVDF/PVP membranes. Hollow fiber membranes were characterized in terms of scanning electron microscopy (SEM), pure water flux and Bovine Serum Albumin (BSA) solute rejection performance in this paper. The experimental result indicated that, as DMAc in the coagulations increased, the pores at the top layer significantly increased, while the sub-layer structure varied differently; Pure water flux of the membrane did not present regularity, but the BSA rejection rate remained relatively stable. when the concentration of DMAc solutions in the first and internal coagulant were up to 70 wt.% and 30 wt.%, the macrovoid structure at the sub-layer were large and loose. It was also found that the pure water flux of the PVDF membranes amounted to 548 L•m-2•h-1 and 270 L•m-2•h-1, which showed a good permeability.

[1] Wang D L, Li K, Teo W K. Preparation and characterization of polyvinylidene fluoride (PVDF) hollow fiber membranes[J]. J Membr Sci, 1999, 163(2):211-220.
[2] 左丹英，徐卫林，徐又一.溶剂对PVDF铸膜液相转化和微孔膜皮-亚两层结构的不同影响[J].高分子学报，2008，6：522-528.
[3] Van’t Hof J A, Reuver s A J, Boom R M. Preparation of asymmetric gas separation membranes with high selectivity by a dual-bath coagulation method[J]. J Membr Sci, 1992, 70：17-30.
[4] Yang Qianz, Chung Tai-Shung, Santoso Y E. Tailoring pore size and pore size distribution of kidney dialysis hollow fiber membranes via dual-bath coagulation approach[J]. J Membr Sci, 2007, 290(1-2):153-163.
[5] 高春梅，孟彦宾，奚旦立.凝胶条件对PVDF/PVC中空纤维膜性能及结构的影响[J].膜科学与技术，2008，28(2)：38-43.
[6] 李战胜，李恕广，江成璋.浸入凝胶法聚合物膜形成机理的研究现状[J].膜科学与技术，2002，22(2)：29-35.
[7] Wijmans J G, Baaij J P B, Smolders C A. The mechanism of formation microporous or skinned membranes produced by immersion precipitation[J]. J Membr Sci, 1983,14:263-274.