Toothed wheel needleless electrospinning: a versatile way to fabricate uniform and finer nanomembrane

Needleless electrospinning is an effective approach to fabricate the nanofibers at high throughput. However, the uniform distribution of nanofibers with finer diameter still needs improvement. In this study, optimization of needleless electrospun polyacrylonitrile (PAN) nanofibers was carried out using an effectively designed toothed wheel spinneret, which improved the nanofiber uniform distribution with finer diameter. Finite element method showed that the electric field norms were highly concentrated at toothed wheel edges. Optimized beadles PAN nanofibers with narrow diameter distribution were obtained at 6 w/v% polymer concentration, 50 kV applied voltage, and 23 cm collecting distance. Highest tensile strength of 100 cN at 7 w/v% concentration showed that the resultant membrane had good mechanical properties. The air permeability of 15 mm/s was obtained at 6 w/v% indicating good insulating behavior of the PAN nanofiber membrane. This study proved that the toothed wheel spinneret has the potential to improve the electrospinning process for the development of uniform nanofibrous membrane at a high production rate.