Quantitative Investigation into the Design and Process Parametric Effects on the Fiber‐Entrapped Residual Charge for a Polymer Melt Electrohydrodynamic Printing Process
Kai Cao, Fucheng Zhang, Ahmadreza Zaeri, Ralf Zgeib, Robert C. Chang
Abstract
Abstract The printing accuracy of the melt electrowriting (MEW) process is adversely affected by residual charge entrapped within the printed fibers. To mitigate this effect, the residual charge amount ( Q r ) must first be accurately determined. In this study, Q r is measured by a commercial electrometer at a nanocoulomb scale for MEW‐enabled scaffolds. Based on this enabling measurement, the effects of various design parameters (including substrate surface conductivity σ , printing time t , layer number N ), and process parameters (including voltage U , translational stage speed v , and material temperature T m ), on Q r are investigated. An increase of σ or decrease of N helps to decrease Q r . The effects of different process parameters on the residual charge can be either dependent or independent of fiber morphologies. Moreover, the fiber‐morphology dependent and independent effect can be either synergistic ( U and T m ) or antagonistic (e.g., v ) for different process parameters. Under same conditions, Q r in the interweaving scaffold design is generally smaller than that in the non‐interweaving scaffold design. These results help to furnish necessary insights into the charge dissipation process for a melt‐based electrohydrodynamic printing process while providing a systematic methodology to mitigate the residual charge accumulation.