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以聚偏氟乙烯(PVDF )/二甲基乙酰胺(DMAc)-正辛醇/水为制膜体系，以腐蚀的合金铝板为制膜基底，采用非溶剂致相转化法制膜，考察了粗糙金属基底对 PVDF 膜结构、性能及其结晶行为的影响。结果显示，金属基底的粗糙微结构对膜的锚固约束不仅减慢了溶剂-非溶剂的传质速率，而且对膜底面有诱导结晶效应；与在光滑基底上所制的 PVDF 膜相比，其膜底面的结晶度与表面粗糙度均增大，水接触角可达133°，且疏水性能稳定；与在砂纸基底上制备的高疏水PVDF膜相比，其气通量和机械强度均有提高。

Abstrac:Polyvinylidene fluoride (PVDF)membranes were fabricated by non-solvent induced phase inversion with the system of PVDF/N,N-dimethylacetamide(DMAc)and 1-octanol/water.DMAc and octanol were used as solvent and non-solvent addition,respectively.In this method,the polymer dope solution was cast on etched alloy aluminum template and the membrane was staying in an environment of constant temperature and relative humidity was about 90% for a certain time.Then it was immersed into water coagulation bath.Effects of the substrate on morphology,performance and crystallization of PVDF membrane were investigated.It was found that the crystallinity and roughness of membrane bottom surface increased which was tailored on etched alloy a-luminum template compared to that on smooth glass sheet.The water contact angle on the bottom surface of the membrane prepared on etched alloy aluminum template reached as high as 133°and the hydrophobicity was stable with time.It was revealed that the membrane could be anchored to the alloy aluminum template,so that the mass transfer rate between solvent and nonsolvent decreased and liquid-solid demixing was promoted.The micrometer-sized morphology of etched alloy aluminum substrate provided induced crystallization.The above-mentioned opinions were confirmed by wide-angle X-ray scattering.The characterization of the PVDF mem-branes obtained by using etched alloy aluminum substrate and waterproof abrasive paper was carried out by a ni-trogen flux measuring and a mechanical property test.It was shown that the highly hydrophobic PVDF mem-brane prepared with etched alloy aluminum substrate was more suitable for industrial-scale production.