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  • A Charge‐Based Mechanistic Study into the Effect of Collector Temperature on Melt Electrohydrodynamic Printing Outcomes
Title: A Charge‐Based Mechanistic Study into the Effect of Collector Temperature on Melt Electrohydrodynamic Printing Outcomes
Abstract Melt electrowriting (MEW) is an emerging additive process for high‐fidelity, microscale fibrous scaffold fabrication. However, achieving precise multilayered MEW‐enabled scaffolds is limited by the entrapped residual charges owing to charge‐based mechanisms. Specifically, the semi‐conductive nature of processed materials causes retainment of net positive charges and jet–fiber repulsion, while exposure to the electric field yields charge polarization with resultant jet–fiber attraction. These competing effects work in tandem to determine the distinctive features of jet–fiber interaction. To deconstruct various charge‐related phenomena, the collector temperature is manipulated as a key process variable to investigate its effect on printing outcomes in two printing modes. Moreover, energy analysis is introduced to explain how collector temperature affects the polarization extent, along with the jet–fiber interaction and printing outcomes. In single fiber printing mode, sets of two parallel fibers with variable set interfiber distances (sSf) are printed at different collector temperatures. At a lowsSfthreshold, significant fiber attraction is observed, but no significant difference is observed among the cases at different collector temperatures. In scaffold printing mode, 200‐layer scaffolds are printed at different collector temperatures, and the wall morphologies are found to vary with location, layer number, and collector temperature.  more » « less
Award ID(s):
1663095
PAR ID:
10388217
Author(s) / Creator(s):
 ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Materials Technologies
Volume:
6
Issue:
7
ISSN:
2365-709X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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