Design and Optimization: Multi-Needle Electrospun MWCNTS/EPOXY Nanofiber Scaffolds for High Volume Production to Enhance Physical and Mechanical Properties of CFRP

Abstract

Electrospinning is the process of ejecting a polymer melt or solution through a nozzle in the presence of a high-voltage electric field, which causes it to coalesce into a continuous filament with anywhere from a micron to submicron diameter, depending on the materials spun and experimental conditions. This process has gained vast attention because of its versatility, low cost, and ease of processing, leading to a huge demand for translating electrospinning experiments out of the laboratory and into commercialized production, and researchers have been thoroughly investigating scaling-up and fulfilling industrial production requirements in terms of throughput, accuracy, and formation of uniform coverage across a multi-nozzle system with vertical spinning.

Our research group previously has developed the fabrication and characterization of submicron carbon nanotube (CNT)–epoxy nanocomposite filaments through an electrospinning process via a single nozzle, horizontal spray process. This is particularly challenging for multi-nozzle systems because each nozzle generates its own standing electric field, leading to electric field gaps (and consequently areas of no coverage) between horizontal nozzles regardless of their spacing. Here in this study, we introduce the scale-up fabrication procedure to identify the most efficient way to address the large volume processing, reproducibility and accuracy, and safety of electrospinning. The electric fields of the experimental multi-nozzle setups were simulated using COMSOL Multiphysics® software to understand the induced surface charges that cause the Taylor cone of the Epoxy/CNT solution to drop on the tip of the nozzles. The electrospinning parameters were also optimized for the multi-nozzle system and analyzed with simulated data to improve stability and fabricate smaller diameter fibers.