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Liquid metal fibers are increasingly used in soft multifunctional materials and soft electronics due to their superb stretchability, high conductivity, and lightweight. This work presents a systematic study of the electrospinning process of liquid metal microfibers. Compared to other methods that usually produce fibers thicker than 100 μm, electrospinning is a facile and low‐cost method of producing liquid metal fibers in the range of 10–100 μm. Specifically, core‐sheath liquid metal microfibers are fabricated with a highly conductive liquid metal core and a super‐stretchable thermoplastic elastomer sheath. This manufacturing process uses a liquid metal emulsion as the core solution, which circumvents manufacturing failures caused by the high surface tension of liquid metals. The influence of key processing parameters such as core flow rate, sheath flow rate, and applied voltage on the fiber diameter and morphology is studied by experiments. The mechanical and electrical properties of the as‐fabricated liquid metal microfibers, mats, and yarns are tested and discussed.
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A quantitative study of the effect of flow on the photopolymerization of fibers
Pulsed-UV light in the continuous flow of a photo-crosslinkable liquid can result in gelation and is a useful method to produce soft microfibers with uniform sizes. With modeling and experiments, we characterize some aspects of this fiber fabrication process. We model the spatial concentration profiles of radical species and molecular oxygen in the flow direction during light exposure, and predict the critical conditions for the onset of fiber formation and compare these predictions with experimental observations. We also characterize the different regimes of microfiber production (no polymerization, non-uniform fibers, and uniform microfibers), qualitatively characterize the rigidity of the fibers, and demonstrate that we can predictably control the length of the produced microfibers for a range of process parameters.
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- Award ID(s):
- 1661672
- PAR ID:
- 10140504
- Date Published:
- Journal Name:
- Soft Matter
- Volume:
- 15
- Issue:
- 46
- ISSN:
- 1744-683X
- Page Range / eLocation ID:
- 9553 to 9564
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/C9SM01485C
