Effect of Electric Field Induced by Collector Shape on the Electrospun Jet Motion and Fiber Structure Evolution

The formation process of beaded structure electrospun fibers in three cases: spherical collector, bowl-shaped collector, and fold-shaped collector, and the influence of electric field on jet motion and the structural evolution of fiber morphology were investigated systematically in this work. In this study, the electric field simulation was performed with the simulation software; The high-speed camera recorded the jet motion, which was characterized using parameters such as the straight jet length, envelope angle,whipping amplitude, and jet velocity. The SEM technique was employed to measure the collected fiber felt. It is found that the different collector systems will have different electric field distributions in the jet area, thus affecting its jet motion and resultant fiber morphology. Observed results showed that the electrospinning system of the spherical collector produced a stronger electric field on the collector surface, which can fully stretch the fibers and beads, producing a smaller bead structure and fewer beads. When the fold-shaped collector was adopted, its surface electric field intensity decreased, resulting in a change in the jet whip, showing a larger envelope angle and whipping amplitude, and the jet velocity decreased slightly, generating a coarser beaded fiber. The surface electric field intensity decreased again when a bowl-shaped collector was employed, the whipping area of the jet was widened, and the speed of the jet decreased again, resulting in the fiber diameter and the bead diameter increasing. The results indicate that the jet motion can be controlled by changing the collector shape to control the electric field intensity distribution, and the desired fibers with different properties are obtained.ent properties are obtained.