Alignment of electrospun polystyrene with an electric field

Polystyrene (PS) with a concentration of 20% by weight in THF/DMF was electrospun on a flat sheet collector. At a concentration of THF above 75%, blocking at the needle tip caused bead formation. However, a nice fiber mat was obtained with the 75/25 THF/DMF. Moreover, at a traveling distance of 10 and 15 cm and voltages from 10 to 16 kV, the PS fibers exhibited alignment. This alignment was reproducible when voltage stabilizer was connected to the voltage supply. This suggested that the uniformly posi-tive charges arising from external voltage interacted with the aromatic rings on the PS chain, yielding a uniform dipole moment. As a result, during jet traveling, the solvent evaporated and the molecules were oriented and frozen at the ground collector.