Study On The Preparation And Properties Of MWNTs/PVA/PEO Compound Electrospinning Fibers

In recent years, with the development of nanotechnology, The ultra-fine fibers and nano-fibers have been widely used Military industry, Biomedical engineering environmental protection and other various fields.Researchers pay great attentions on electrospinning because it is a convenience, direct, simple and unpolluted method for nano-fiber preparation.At present, there is kinds of polymer which can be used to produce nano-fibers by electrospinning.Polyvinyl alcohol(PVA), with its good into fiber forming property, crystalloid, higher interface activity,plays the important raw as electrospinning materials. So, it is very important to research PVA fiber prepared by electrospinning.However, PVA is a kind of low molecular weight polymer low viscosity in peroxide solution,so,PVA is poor in spinnability. It is difficult for single PVA solution to prepare PVA fiber by electrospinning. Polyoxyethylene(PEO), which is also non-toxic, harmless, but has great viscosity, high spinnability in low density solution. Therefore, in this article little PEO is put in PVA solution to improve its spinnability.As Carbon nanotubes (CNTs) has special geometric dimension and structure which give it excellent properties, it's recognized as the best adding material that can improve the performance of polymers. Because the big aspect ratio, high surface energy and easy agglomeration of CNTs, so it has an effect on the dispersion property in the polymer and compatible property with polymer matrix.So, PVA is used to disperse MWNTs in this subject,then PEO solution is mixed with the PVA/MWNTs suspension. Finally MWNTs/PVA/PEO fiber is prepared by electrospinning, and study on the Structure and performance of the fibers.MWNTs were dispersed in PVA solution with the concentration of 0.1%-1%, and dispersivity were characterized by UV spectrophotometer then Chosed the best suspension of MWNTs/PVA stability and PEO electrostatic spinning via solution blending.The fibers that with small diameter and uniform thickness were prepared by the best electrostatic spinning processes that obtained by orthogonal experiments and the MWNTs/PVA/PEO fibers with different content of mwcnts in the best spinning processes, at last, the structure,crystallinity and thermal stability of fibers were characterized by SEM,XRD and DSC respectively. the following conclusions were drawed.1.PVA is an effective dispersant to disperse MWNTs, and to scatter 0.2g MWNTs,the best concentration of PVA is 0.5%.2. The voltage was the most important influencing factor on the diameter of fiber and the optimal conditions is voltage 90 Kv, receiving distance 40 cm, needle diameter 0.45 mm. The thinnest fiber diameter was 213nm.3.With the increasing of MWNTs content, The avenage diameter of composite ultra-fine fiber was thinner; the crystallization of PVA was decreased,but the crystallization of PEO was unchanged; the thermal stability of fibers are firstly increased then reduced; and the electrical conductivity of fibers was improve.