UC Irvine

Nanofiber produced by electrospinning has been used in a wide range. However, in traditional electrospinning, a bending instability occurs as the fiber travels from the needle to a collecting substrate due to charge interactions which causes the fibers to deposit on the collector randomly. A new form electrospinning called near-field electrospinning(NFES) has been discovered in last decades. This technology allows a good control of nanofibers, makes it feasible to draw nanofibers in a certain pattern without bending instability happened in traditional electrospinning. Also, NFES decreases voltage applied to setup from thousands of volts to hundreds of volts, making the electrospinning process cheaper and safer. But this new form technology still has limitations. Since NFES decreases working distance between needle and substrate to millimeter scale and since polymer droplet size is small. Getting a good control of electrospinning initiation process is difficult to achieve. This thesis demonstrates the feasibility of using electrostatic forces to get a good control of initiation process and make the whole process predictable. In addition, relationship between thickness of nanofibers and key experimental parameters such as initiation tip size, working distance, voltage and droplet size are studied in this thesis using finite element analysis.