聚合物分子量对浸没沉淀法制备PVDF微孔膜结构与结晶的影响  

Effect of Polymer Molecular Weight on the Morphology and Crystallization of Prepared PVDF Membranes

作　　者：王许云[1,2] 赵书菊[1] 张林[2] 陈欢林[2] 

机构地区：[1]青岛科技大学化工学院,山东青岛266042 [2]浙江大学化学工程与生物工程学系,浙江杭州310027

出　　处：《高分子材料科学与工程》2010年第9期76-79,共4页Polymer Materials Science & Engineering

基　　金：国家支撑计划项目(2006BAB03A06);中央高校基本科研业务费专项资金资助(KYJD09011);山东省泰山学者建设工程项目(JS200510036)

摘　　要：聚合物的分子量对浸没沉淀法制备聚偏氟乙烯(PVDF)微孔膜结构和结晶具有较大影响。随着聚合物分子量的增大,所成膜上表面孔尺寸和孔密度有减小的趋势。分子量较大的PVDF所成膜的底面及膜内指状孔表面均为完全无孔致密结构。断面指状孔下方为相互连通的海绵状结构。当聚合物的分子量较低时,断面开始由相互连通的海绵状结构向胞腔状结构过渡。由低分子量的PVDF制得的膜,结晶类型既有α型结晶,又有β型结晶。由高分子量的PVDF制得的膜,主要为α型PVDF结晶。后者的结晶度明显大于前者。Polyvinylidene fluoride（PVDF） membranes were prepared by immersion precipitation method. Effect of the polymer molecular weight （M-v） on the morphology and crystallization of prepared membranes was examined. With the M-v increasing of the polymer,the mean pore size and pore density of the top surface of the prepared membranes have the tendency of decrease. For PVDF with high M-v,the morphology of the prepared membrane is fingerlike structures with sponge substrate beneath the dense skin in cross section. For PVDF with low M-v,the morphology of the prepared membrane is from sponge substrate to globule-like structure beneath the porous skin in cross section. For the membranes prepared with high M-v polymer,the crystallites are composed by ＂α＂ crystallite and ＂β＂ crystallite,while the crystallites are mainly ＂α＂ crystallite for that of the membrane prepared with low M-v polymers. The crystallites degree of the former is higher than that of the later evidently.

关 键 词：聚偏氟乙烯 相转化 分子量 结晶 

分 类 号：TQ325.4[化学工程—合成树脂塑料工业]