Preparation And Application Of Poly (Vinyl Alcohol) Nanofibers By Electrospinning

In this paper, the PVA, PVA/SWNTs and PVA/Ag nanofibers were prepared by electrospinning and the various parameters which could affect the electrospinning process were studied. The results show that voltage, polymer concentration, receiving distance and even environmental factors could impact on the fiber morphology. Before added to the PVA solution, the SWNTs were dispersed ultrasonically. Then the PVA/SWNTs nanofibers were produced by electrospinning. SWNTs concentration was important factor which could affect the fiber morphology. It is very important for crosslinking the PVA nanofibers because of the high hydrophilicity of PVA. There were two methods to crosslink nanofibers:chemical crosslinking method and physical crosslinking method. The result shows that the nanofibers could still maintain its structure after immersing in water by physical crosslinking method-the heat treated. Then the heat treated mats were soaked in Tollens, experiencing washing process, and reduced by glucose finally. Through varying washing times, Tollens concentration, and soaked-reduced times, we obtain the Ag midnanoparticles which coating degree and size are tunable. In addition to this, we tried to add AgNO3to PVA solution. The PVA/AgNO3nanofibers were prepared from a PVA/AgNO3aqueous solution by an electrospinning process. They were prepared into two types of PVA/AgNO3nanofibers:One was electrospun from PVA/AgN03aqueous solution and then the electrospun nanofibers were treated with UV radiation and heat; the other one was electrospun from PVA/AgNO3solution treated with UV radiation. Finally, calcination of the nanofibers which were soaked in Tollens and reduced by glucose produced smooth pure silver nanofibers. The antibacterial activities of various PVA/Ag and PVA/AgNO3nanofibers were examined against E.coli. It turned out that the Ag nanoparticles successfully inhibited the growth o f the bacteria.