Effect of solution concentration, process parameters and a second electric field on electrospun polyamide-11 fibers

Journal of Industrial Textiles, vol. 55

Abstract

The electrospinning process parameters for producing polyamide 11 (PA11) nanofibers using formic acid (FA) as the solvent were investigated. Key variables such as solution concentration, tip-to-collector distance, applied voltage, flow rate, and the introduction of a second electric field were optimized to produce uniform, bead-free nanofibers. Preliminary studies indicated that a 10% (w/v) PA11/FA solution concentration, a 25 kV voltage applied to the collector, a 12 cm tip-to-collector distance and a flow rate of 0.03 mL/min yielded the most consistent results in a conventional nozzle electrospinning setup. The effects of distance, voltage, and flow rate on fiber morphology were examined, with increased distance producing thinner fibers due to improved solvent evaporation, while higher voltages resulted in thicker fibers, highlighting the complex interplay between these parameters. Flow rate also played a significant role in fiber formation. The incorporation of charged metallic rings along the jet path, introducing a second electric field, further improved fiber uniformity. The most significant effect on the morphology of electrospun PA11 fibers was observed with rings connected to increasing voltage values, resulting in fibers with an average diameter of 145.7 ± 23.7 nm, minimal bead formation, and uniform circular cross-section. These optimized electrospinning parameters and the application of a second electric field show potential for improving fiber quality in applications such as filtration, textiles, and tissue engineering, contributing to a deeper understanding of PA11 electrospinning.

Authors 3

1. Teresa Raquel Barata corresponding

   University of Beira Interior

   Affiliation as printed

   Department of Textile Science and Technology, Faculty of Engineering, University of Beira Interior, Covilhã, Portugal

   Fiber Materials and Environmental Technologies (FibEnTech-UBI), Universidade da Beira Interior, Covilhã, Portugal

2. Roshan Paul Aachen Institut für Textiltechnik

   RWTH Aachen University

   Affiliation as printed

   Institut für Textiltechnik der RWTH Aachen University, Aachen, Germany

3. Nuno Belino

   University of Beira Interior

   Affiliation as printed

   Department of Textile Science and Technology, Faculty of Engineering, University of Beira Interior, Covilhã, Portugal

   Fiber Materials and Environmental Technologies (FibEnTech-UBI), Universidade da Beira Interior, Covilhã, Portugal