支撑型复合高分子膜材料的制备与表征

采用浸没沉淀法、织物为支撑体制备复合型高强度膜材料.提出了支撑材料的筛选方案,研究了带支撑的复合膜在成膜过程中的起皱原因,并成功制备了支撑型复合膜.考察了不同质量分数的聚偏氟乙烯(PVDF)、聚砜(PSF)收缩率、拉伸强度、平均孔径、纯水通量等因素对复合膜性能的影响.采用膜通量、孔径分析、力学强度、扫描电镜( SEM)、收缩率对复合膜进行分析与表征.结果表明:高分子材料在成膜过程中的收缩与支撑材料的收缩的差异可能是起皱的重要原因.收缩率大于50％,起皱收缩明显；收缩率低于40％,复合膜平整.所制备的高强度复合膜的拉伸强度大于35 MPa,膜孔径为0.07～0.6μm,水通量为5 000～ 17 000 L/(m2·h·MPa).

Preparation and characterization of reinforced polymeric membrane with fabric support

Fabric reinforced high strength composite membranes were prepared by immersion phase separation. Different supporting materials were tested and a selection criterion was suggested.The effects of the operational conditions were as follows:the shrinkage of polyvinylidene fluoride(PVDF) or polysulfone (PSF),the tensile strength,the mean pore size,and the pure water permeation in different concentration polymer solutions.The composite membranes were characterized by pure water permeation,pore size, strength,scanning electron microscop(SEM),and shrinkage.The results showed that the shrinking difference in the polymer materials played a key role in determining the adhesion of the polymeric membrane material and fabric in that a lower degree of shrinkage led to good composite membranes.The shrinkage rate was greater than 50%,wrinkling obvious;the shrinkage rate was less than 40%,composite membrane formed.Finally,a high-strength composite membrane was prepared with a pore size of 0.07～0.6μm, pure water flux of 5 000～17 000 L/(m~2·h·MPa),and a tensile strength of 35 MPa.