doi: 10.3850/978-981-11-0749-8_723
Corner Deposition on Near-Field Electrospinning for Pin-To-Pin and Pin-To-Plate Electrode Configurations
Nicolas Martinez-Prieto, Jian Cao and Kornel Ehmann
Dept. of Mechanical Engineering, Northwestern University, Evanston, IL 60208, USA
Abstract
Near-field electrospinning (NFES) has been proposed as a direct writing method for micron-sized structures with high resolution. We have previously reported the limitations of the technique in terms of accuracy and repeatability when depositing corners. The limitations are thought to arise from the acceleration and deceleration of the collector and from fiber-fiber interactions. To address accuracy limitations at corners, dwell times are added to the collector path at the corners to allow for the fibers to reach the desired locations. The effect of these dwell times is studied for pin-to-pin and pin-to-plate electrode geometries. The results show that the dwell time allows for the production of 90° and repeatable corners. The ideal dwell time depends on numerous process parameters including collector speed, travel distance, and electrode configuration. The value can vary from tens of milliseconds to a few seconds. The quality of the corners produced using a pin-to-pin geometry was inferior to that of a pin-to-plate one; longer dwell times were required to achieve perpendicular corners for pin-to-pin configurations. This is a surprising result as electric field focusing in pin-to-pin configurations was expected to improve deposition accuracy.
Keywords: Near-field electrospinning, Fiber fabrication, Corner deposition.
