Studies on the Relationship between Morphology and Water Flux of PVDF/PU Blend Membranes

摘要

Polyvinylidene fluoride/polyurethane (PVDF/PU) blend membranes were made via immersion precipitation process,the surface morphologies and the micro-porous structures of the blend membranes were analyzed using scanning electronic microscope (SEM) and fractal theory,thc water flux change with the operation pressure of the blend membranes was investigated,and the relationship between blend membrane morphology and water flux was discussed.The results showed that,the water flux of the resulting blend membranes was increased,and the contribution of different structures to water flux was in the following order:cross-section finger-shaped porous defects ＞ cross-section through holes ＞ blend membrane surface pores.In addition,water flux of the blend membranes was also related to the deformability of PU.