【作者】 王帅；

【导师】 卫英慧；

【作者基本信息】 太原理工大学 ， 材料学， 2010， 硕士

【摘要】 高压静电纺丝法是一种制备纳米纤维的简单方法,具有方便直接无污染的特点。与普通纤维相比,由高压静电纺丝制备的纳米纤维具有较大的比表面积和较高的吸附性,近年来引起了国内外研究者的极大关注。本文选用聚乙烯醇(PVA)、聚氧化乙烯(PEO)两种水溶性的高分子材料为原料,以水为溶剂制备静电纺丝纤维。采用正交实验法分析研究了静电纺丝的工艺参数对PVA/PEO共混纳米纤维形态的影响。将具有独特的力学、电学等理化性质的碳纳米管(MWNTs)添加到PVA/PEO共混体系中,以制备PVA/PEO/MWNTs复合纳米纤维。为了能使碳纳米管在聚合物体系中有良好的分散,本文还对碳纳米管进行了纯化及分散处理,并研究了碳纳米管的添加量、添加方式及长径比对复合纤维形态及结构的影响,以期获得综合性能优异的导电聚合物复合纤维材料。采用PVA和PEO物理共混溶液为静电纺丝溶液,进行单因素纺丝实验和综合三因素三水平(3 x 3)的正交试验。通过正交分析,得到制备超细纤维的最优条件为:电压90 kV(-);接收距离30 cm;针头直径5.5 mm。制得了平均直径最细达到590 nm纤维。将经过纯化和分散的多壁碳纳米管(MWNTs)添加到PVA/PEO共混水溶液中,利用静电纺丝技术制备PVA/PEO/MWNTs复合超细纤维。结果表明:十二烷基硫酸钠(SDS)可使纯化后的MWNTs在水溶液中具有较好的分散稳定性。得到的复合超细纤维的平均直径随MWNTs添加量的增加而减小。未添加MWNTs时,纤维平均直径为857 nm;当MWNTs的添加量为1.5 wt %时,纤维平均直径达700 nm,且表面光滑,分布均匀。用PVA分散的碳纳米管悬浮溶液以溶剂的形式加入到聚合物溶液中可使碳纳米管的分散性更好,进而有利于纺丝的进行。随着碳纳米管的含量从0.27%增加到0.53%,纤维直径下降,最细可达368 nm。当碳纳米管的含量增加到一定量时,溶液的导电性下降,使纤维的直径又有所增加。添加大长径比碳纳米管(large aspect ratio MWNTs即L-MWNTs)的聚合物溶液纺丝得到的纤维直径比添加小长径比碳纳米管(small aspect ratio MWNTs即S-MWNTs)的纤维直径更细。更多还原

【Abstract】 Electrospinning is a convenience, direct and simple method for nano-fiber preparation. Compares with the ordinary fiber, nano-fibers prepared by electrospinning has larger surface area and the high adsorbability,which in recent years attracted great attention at home and abroad.In this study, two kinds of water-soluble high polymer material, the polyvinyl alcohol (PVA) and the polyoxyethylene (PEO), were selected as raw materials, and water was taken as solvent to prepare electrospinning fibers. Orthogonal experiment was used to analysis the influence of electrospinning process parameters on PVA/PEO compound nanofibers morphology. MWNTs which has unique physics and chemistry character were added into PVA/PEO blending system to prepare the PVA/PEO/MWNTs compound nano-fiber. In order to have the good dispersion in the polymer blending system, MWNTs was purified and dispersed .The influences of the addition content , the addition method and the aspect ratio of carbon nanotubes on morphology and structure of composite fibers were also studied. The composite fibers has potential applications in electric conduction.PVA/PEO physics blending solution was used as electrospinning solution, electrospinning of single factor, orthogonal experiments with three factor and three levels (3 x 3) were carried. The results showed that optimal conditions is voltage 90 kV(-), receiving distance 30 cm , needle diameter 5.5 mm . The thinnest fiber diameter was 590nm .After being purified and dispersed , MWNTs were added into PVA/PEO blending aqueous solutions to prepare PVA/PEO/MWNTs composite ultra-fine fiber. The results showed that MWNTs have good dispersion stability in aqueous solutions after dispersed by SDS . The avenage diameter of composite ultra-fine fiber increases with decreasing addition content . When there is no MWNTs in blending aqueous solutions , the fiber average diameter is 857 nm ; when the addition content of MWNTs is 1.5 wt % , the fiber average diameter is 700 nm, and surface of fibers is smooth , distribution is uniform .When MWNTs dispersed by PVA were added as solvent to prepare polymer solution, the dispersion of MWNTs aqueous solutions becomes better . After electrospun, With increasing MWNTs content , the fiber diameter decreases ; when the MWNTs content increases from 0.27% to 0.53% , the fiber diameter decreases to 368nm . When the MWNTs content increases to a certain value , the conductivity of the solution decreases, the fiber diameter increases . The diameter of the fiber electrospun by the polymer solution added with L-MWNTs is smaller than that added with S-MWNTs .更多还原