Effects of polymer/solvent systems on electrospun polyvinylpyrrolidone nanofiber morphology and diameter

In this paper, the relationship between the rheological properties of polyvinylpyrrolidone solutions and the morphology of their electrospun fibers was established. The viscosity, surface tension, and electrical conductivity of the polymer in DMF and ethanol were measured in the concentration range of 5-30 wt %. Electrospinning of polymer solutions was carried out under controlled parameters. To obtain uniform and bead-free nanofibers, it was evident that the minimum solution concentration must be chosen at 12 and 8 wt % in DMF and ethanol, respectively. Uniform nanofibers without beads were obtained from electrospinning of polymer solutions in DMF in the range of concentration 12-20 wt %. In ethanol nanofibers with wide diameter distribution could be obtained, so it is suitable for microfiber production.