Study on Wet Electrospinning Process

Electrospinning was carried out in an insulating liquid, Fluorinert FC-40 (Sumitomo 3M Ltd.), to judge whether "wet electrospinning" is practicable or not. Chloroform, N,N-dimethylformamide, and their mixture of 1 to 1 are used as a solvent of polystyrene. Among the three solvents of spinning solutions, only chloroform was fit for wet electrospinning in Fluorinert FC-40. Effect of polystyrene concentration was investigated using spinning solutions of chloroform solvent. Polystyrene particles and fibers were formed from the solutions of 5 to 15wt% polystyrene spinning solutions. From 20wt% solution, only fibers with many beads were formed, and from 25wt% solutions only fibers without beads were formed. The diameters of fibers formed were increasing with an increase in the concentration. The diameter was about 10um and 50um for fibers from 20wt% and 25wt% solutions, respectively. It is concluded that wet electrospinning is practicable. However, improvement of apparatus and process will be necessary to produce non-woven fabric of nanofibers.