Simulation design and experimental study of beveled angle narrow-slit needleless electrospinning spinneret

Needleless electrospinning technology is considered an effective way to produce nanofibrous materials on a large scale. The electric field strength and its distribution during the electrospinning process play an essential role in controlling the diameter and quality of the nanofibrous membrane. To achieve the mass production of nanofibers, this study proposed the design concept of a new type of needleless electrospinning spinneret with a beveled tip and narrow slit shape. The finite element analysis software of Comsol Multiphysics 6.0 was used to simulate the electric field contour of the new type of needleless electrospinning spinneret with a beveled tip and narrow slit shape. In performing the simulation of electrospinning with this spinneret, the values of the electric field strength on the surface of the spinneret and the variation of its electric field strength distribution curve were obtained. The optimal beveled narrow-slit spinneret structure was determined by varying the beveled tip angle, inner ring material, applied voltage, and receiving distance. The results showed that the highest value of electric field strength at the tip of the spinneret could be obtained when the inner ring was made of PTFE and the beveled narrow-slit spinneret was at 120°. Finally, the polyurethane nanofiber membrane was successfully fabricated using this new type of electrospinning spinneret. The nanofiber membrane with a mass fraction of 17% had a good micro-morphology. The diameter distribution was very uniform, and the average diameter was 624 nm. The production was up to 9.6 g/h, which was 96 times higher than that of single-needle electrostatic spinning. The feasibility of mass production of nanofiber membranes using this novel spinneret was verified.