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Abstract The covid‐19 pandemic has revealed the need for alternative production approaches with low startup costs like electrospinning for filter needs, the most imperative element of the personal protective equipment (PPE). Current attempts in advancing melt electrospinning deal with developing strategies for fiber diameter attenuation toward sub‐micron scale. Here, the attunement in the spinning‐zone temperature known as ''spin‐line temperature profile'' was utilized as a baseline for fiber diameter reduction. The mechanical performance of the melt‐electrospun linear low‐density polyethylene (LLDPE) fibers is reported to characterize their structural transformation with respect to various spin‐line temperature profiles. With an increase in the spin‐line temperature to above 100°C in the area of cone formation, an increased tensile and yield strength along with fiber diameter reduction by four‐folds was demonstrated. A significant increase in toughness, by almost three times, without compromising the stiffness and Young's modulus was observed. The dynamic mechanical analysis revealed that spinning in high temperatures produces changes in the alpha (α) relaxation, contributing to the significant increase in strain at break. These results are significant because polyolefin fibers are an imperative element of medical textiles and PPE. Therefore, developing a correlation for process‐structure‐properties for emerging production techniques like melt electrospinning becomes critical.
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This content will become publicly available on December 19, 2025
Gravity-Driven Ultrahigh-Speed Electrospinning for Green Production of Ethyl Cellulose Nanofibers with Tunable Porosity for Oil Absorption
ABSTRACT: Ethyl cellulose (EC) is a biocompatible, renewable, and recyclable material with diverse sources, making it an attractive candidate for industrial applications. Electrospinning has gained significant attention for the production of EC fibers. However, conventional electrospinning methods face challenges such as bead formation, low yield, and the absence of porous internal structures, limiting both the functional performance and scalability. This study presents an optimized approach for producing EC fibers by using a gravity-driven ultrahigh-speed electrospinning (GUHS-ES) system. This system leverages gravity to reshape the Taylor cone morphology during electrospinning, enhancing stability and dramatically increasing throughput. As flow rates increase, the Taylor cone contracts inward, while the tip structure expands and stabilizes, reaching maximum size at ultrahigh flow rates (100−150 mL/h). This unique Taylor cone structure enables a fiber production rate of 24.5 g/h, hundreds of times greater than conventional electrospinning techniques. Another advantage of the GUHS-ES system is its ability to achieve both high diameter uniformity and adjustable porosity. At ultrahigh flow rates, the pore sizes of the EC fibers reached 321 nm. The highly porous structure of EC fibers exhibited an absorption capacity of 56.6 to 110.7 times their weight, exceeding most previously reported oil-absorbing materials and demonstrating high efficacy for rapid waste oil absorption. This green, efficient technology represents a promising advancement for the large-scale production and application of natural polymer fibers with broad implications for sustainable industrial processes.
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- Award ID(s):
- 2247399
- PAR ID:
- 10617668
- Publisher / Repository:
- ACS
- Date Published:
- Journal Name:
- ACS Sustainable Chem. Eng.
- ISSN:
- 2168-0485
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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