POLYACRYLONITRILE-BASED CARBON NANOFIBERS PREPARED BY ELECTROSPINNING

摘要

Electrospinning could be a cost effective method to produce novel fibers whose diameters range from few nanometers to several microns. The high specific surface area of ultrafine fibers can be used as high performance filters, scaffolds in tissue engineering, sensors, composites and in radiation shielding. Polyacrylonitrile (PAN) nanofibers were produced using electrospinning by dissolving polyacrylonitrile in N,N-dimethylformamide (DMF) solution. The spinning was carried out for 10, 15 & 20% (by weight) concentrations at different voltages, flow rates, varying distance between needle and collector and at different needle diameters. The electrospun fiber was collected by attaching it to stainless steel foil wrapped on a drum of diameter 4.5 inch rotating at various speeds. The electrospun fiber web was stabilized by heating at 280°C for 1 hour in air. The stabilized nanofiber webs were carbonized at 700°C in an inert atmosphere. The spunned fibers were characterized using scanning electron microscope. The aligned fibers (around 80%) were formed by rotating drum at ～1000 rpm. At lower speeds the fibers were not aligned. The diameter of the fiber decreased with increase in stabilized and carbonization temperatures. The char yield was found to be around 63%.