Experimental investigation of the governing parameters in the electrospinning of polyethylene oxide solution

Electrospinning is an old but yet immature process which is now used to form nanoscale polymer fibers. This paper describes the use of SEM and measurements of jet currents to investigate the effects of key parameters on fiber formation during electrospinning of a polyethylene oxide solution (PEO). The ambient humidity and voltage polarity are key factors influencing fiber formation, but this process has not been carefully analyzed. The influence of the ambient humidity can be overcome by choosing a solvent with a larger difference between the saturated vapor pressure and the actual vapor pressure in air or by lowering the ambient humidity when water is used as the solvent. The process works with both negative and positive voltages, but the polarity influences the stability and the fiber diameters. Variations of the current were found to correspond with variations of the fiber diameters. Short target distances were found to prevent fiber formation while long distances resulted in a larger distribution of fiber diameters. The experiments also showed that ultra fine fibers were found between the ends of broken fibers due to a strong electrical force on fibers with little solvent