以聚偏氟乙烯为膜材料,二甲基亚砜为溶剂,通过相转化法制备不对称结构的聚偏氟乙烯微孔膜.考察不同凝胶浴组成浓度对膜结构和性能的影响.结果表明,二甲基亚砜容纳非溶剂水的能力非常弱.以二甲基亚砜为溶剂时,所成膜均为指状孔和球晶共存的结构.凝胶浴的组成将影响成膜机理,随着凝胶浴浓度的不断增大,凝胶分相延迟发生,指状孔的尺寸也随之增大,因此成膜孔隙率和水通量都逐渐升高.当凝胶浴为60%DMSO时,所成膜的孔隙率为78%,水通量达到623 L/m2h.%Asymmetric poly(vinylidene fluoride)(PVDF) membranes were prepared by immersion precipitation in the H2O/ dimethylsulfoxide(DMSO) / PVDF system.The effects of different bath content on structures and performances of PVDF membranes were investigated.By using DMSO as solvent,the cast membrane exhibited a large number of short finger-like cavities and globules.It was found that the DMSO in the bath hindered the phase-separation kinetics.The size of finger-like cavities increased with the increase of dimethylsulfoxide in the bath.As a result,the porosity and pure water flux of PVDF membranes also increased.With the bath content of 60% DMSO,the porosity of resulting membrane was 78%,and pure water flux was up to 623 L/m2h.
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