The Effects of Operating Parameters on the Morphology of Electrospun Polyacrilonitrile Nanofibres.

Polyacrilonitrile (PAN) nanofibres were prepared by electrospinning of PAN/DMF solution of 15 % wt concentration. Fibre morphology was observed under a scanning electron microscopy. The effects of operating parameters including applied voltage, feeding rate and tip-target distance on the morphology of electrospun PAN nanofibres were systematically evaluated. Average diameters of nanofibres decreased with increasing applied voltage from 10 to 20 kV, but broader distribution in diameters of nanofibres were obtained at 15 kV and above. Morphology of nanofibres was changed by the instability of the liquid surface from which the jet originates to beaded nanofibres. The morphological structure can be changed by changing the feeding rate of solution and tip-target distance. At lower and higher feeding rates, nanofibres with beades were observed. At 7.5 cm tip-target distance and below, the structures of nanofibres appeared not to be stabilized completely, indicating that the spun nanofibres were mostly wet when they reached the collecting target.