采用静电纺丝/非溶剂致相分离制备聚丙烯腈多孔超细纤维的研究  

PREPARATION OF POROUS POLYACRYLONITRILE ULTRATHIN FIBERS BY ELECTROSPINNING WITH NONSOLVENT INDUCED PHASE SEPARATION

作　　者：欧洋[1] 吴青芸[1] 万灵书[1] 杨皓程[1] 徐志康[1] 

机构地区：[1]高分子合成与功能构造教育部重点实验室浙江大学高分子科学与工程学系,杭州310027

出　　处：《高分子学报》2013年第2期248-254,共7页Acta Polymerica Sinica

基　　金：国家自然科学基金(基金号21174124)资助项目

摘　　要：以聚丙烯腈/二甲基亚砜/N,N'-二甲基甲酰胺三元体系为纺丝液、3℃水浴为接收介质,通过静电纺丝制备了具有纳米孔结构的静电纺聚丙烯腈多孔超细纤维.探讨了溶剂比例、接收介质、聚丙烯腈浓度、纺丝电压及接收距离等因素对纤维直径和表面孔隙率的影响.结果表明最佳制备条件为混合溶剂质量比1∶1、纺丝电压16 kV、聚丙烯腈浓度15 wt%、接收距离5 cm、纺丝速率0.7 mL/h、环境温度25℃、相对湿度40%～70%.在此条件下得到的聚丙烯腈多孔超细纤维直径在420～490 nm,平均直径468 nm,表面孔隙率3.4%,纤维内部形成大量孔径为8～30 nm的孔结构,且孔径分布均匀,孔形状相对一致.N2吸附脱附测试表明,聚丙烯腈多孔纤维的BET比表面积达43.86 m2/g,是相同直径无孔聚丙烯腈纤维比表面积理论值的6倍.通过研究聚丙烯腈/(二甲基亚砜+N,N'-二甲基甲酰胺)/水的三元相图,提出非溶剂致相分离是主要成孔机理.Porous polyacrylonitrile （PAN） ultrathin fibers with nanopore structures were prepared by electrospinning a ternary system of PAN/dimethyl sulphoxide （DMSO）/N, N＇-dimethylformamide （DMF） using a water bath at 3 ℃. We investigated the effects of proportion of DMSO to DMF, collection medium, PAN concentration, applied voltage and needle to collector distance on the diameter and surface porosity of PAN uhrathin fibers. The optimum electrospinning parameters are given as PAN concentration of 15 wt% , DMSO/ DMF proportion of 1 ： 1 （W/W） , applied voltage of 16 kV, needle to collector distance of 5 cm, solution flow rate of 0.7 mL/h,relative humidity of 40% ～ 70% and room temperature of 25℃. The diameter, morphology and porosity of porous PAN ultrathin fibers were characterized by scanning electron microscope, showing the fibers,which were obtained under the optimum conditions,were porous throughout with a diameter ranging from 420 nm to 490 nm, an average diameter of 468 nm and surface porosity of 3.4%. The BET specific surface area was measured by nitrogen adsorption and desorption isotherms. It can reach 43.86 m2/g,which is 5 times higher than the theoretical surface area of smooth and nonporous 468 nm PAN fibers. Moreover, nonsolvent induced phase separation has been proposed to be the main mechanism for the formation of porous PAN fibers, which is confirmed by the ternary phase diagram of PAN/（DMSO ＋ DMF）/H20.

关 键 词：聚丙烯腈 静电纺丝 多孔结构 非溶剂致相分离 

分 类 号：TQ342.93[化学工程—化纤工业]