辛醇对PVDF膜表面浸润性与透过性能的影响  

Effect of Octanol on Wettability and Permeability of PVDF Porous Membrane via Dry-Wet Phase Inversion

作　　者：王志英[1] 李建林[1] 孔祥森[1] 杨振生[1] 李春利[1] 

机构地区：[1]河北工业大学化工学院,天津300130

出　　处：《天津大学学报》2011年第7期628-632,共5页Journal of Tianjin University(Science and Technology)

基　　金：河北省自然科学基金资助项目(B2008000016)

摘　　要：以聚偏氟乙烯(PVDF)/N,N-二甲基乙酰胺(DMAc)/辛醇/水为制膜体系,采用干、湿相转化法制膜.考察了辛醇含量对膜结构、表面浸润性和透过性能的影响.结果表明,辛醇的加入使成膜过程中液-固分相在与液-液分相的竞争中占据优势,随着辛醇含量的增加,膜结构由海绵状结构向球晶堆积结构转变,当辛醇含量增至10%时,生成"菜花状"球晶粒子堆积的对称结构,其表面具有微纳二重特征,对水的接触角可达140°;实验范围内PVDF膜下表面的疏水性随铸膜液中辛醇含量的增加先增大后略有下降,膜的气通量随铸膜液中辛醇含量的增加先增大后减小.所制得的高度疏水膜可望成为气液膜接触器的理想膜材料.Hydrophobic polyvinylidene fluoride（PVDF）membranes were tailored by dry-wet phase inversion with the system of polyvinylidene fluoride（PVDF）/N,N-dimethylacetamide（DMAc）and octanol/water.The effects of octanol content on the morphology,wettability and permeability of PVDF membrene were investigated.PVDF is a semi-crystalline polymer,therefore,there exists the competition of liquid-liquid demixing and liquid-solid demix-ing.Adding octanol into the solvent made the liquid-solid demixing occupy the predominant position as competing with liquid-liquid demixing.The membrane morphologies transited from spongy structure to nodule-like structure with increasing octanol content.The membrane exhibited cauliflower-like spherulitic particles and symmetric morphologies when octanol content increased to 10%.The particles had a diameter of 5—10,μm and nanoscale papillas appeared on the particles.The micro-and nano-scale hierarchical roughness on the bottom surface brought about an enhanced hy-drophobicity of the membrane.The contact angle of the membrane with water was as high as 140°,exhibiting high hydrophobic property.In the experimental range,the water contact angle increased and then decreased slightly with increasing octanol content;the nitrogen flux increased and then decreased obviously with increasing octanol content.The well controlled structure makes these membranes ideal interfaces to be processed in membrane contactors.

关 键 词：聚偏氟乙烯(PVDF) 膜 相转化 非溶剂添加剂 疏水性 接触角 

分 类 号：TS102.54[轻工技术与工程—纺织工程] TQ028.8[轻工技术与工程—纺织科学与工程]