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Electrospinning is a straightforward approach for efficiently creating continuous fibers within the submicron to nanometer size range. Electrospun fibers possess excellent properties like high porosity, large specific surface area, tunable morphology, small diameter, etc., making them desirable in various applications. Because of its various properties, polymer is one of the most used materials as the spinning solution in electrospinning. Electrospun polymeric fibers, by themselves, may serve limited applications. Therefore, they are usually mixed with other materials to serve many applications. There are many ways in which these other materials are mixed with polymers in electrospinning, like doping, surface treatment, functionalization, etc. There are several studies published that report on the various composite fibers produced using electrospinning. However, a review focused solely on the production of heterogeneous fibers, where the electrospun fibers are intrinsically made of more than one material, is lacking. Herein, we review different heterogeneous fibers synthesized using electrospinning and their fabrication methods.
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Effect of the spin‐line temperature profile on the mechanical properties of melt electrospun polyethylene fibers
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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- Award ID(s):
- 1635113
- PAR ID:
- 10452964
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Applied Polymer Science
- Volume:
- 138
- Issue:
- 28
- ISSN:
- 0021-8995
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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