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The development of fibrous actuators with diverse actuation modes is expected to accelerate progress in active textiles, robotics, wearable electronics, and haptics. Despite the advances in responsive polymer-based actuating fibers, the available actuation modes are limited by the exclusive reliance of current technologies on thermotropic contraction along the fiber axis. To address this gap, the present study describes a reversible and spontaneous thermotropic elongation (~30%) in liquid crystal elastomer fibers produced via ultraviolet-assisted melt spinning. This elongation arises from the orthogonal alignment of smectogenic mesogens relative to the fiber axis, which contrasts the parallel alignment typically observed in nematic liquid crystal elastomer fibers and is achieved through mesophase control during extrusion. The fibers exhibiting thermotropic elongation enable active textiles increase pore size in response to temperature increase. The integration of contracting and elongating fibers within a single textile enables spatially distinct actuation, paving the way for innovations in smart clothing and fiber/textile actuators.
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Wash‐stable electrospun piezopolymer textiles
Abstract Smart textiles are currently being pursued for actuation and sensing for their potential to directly incorporate “intelligence” into the fabric, in contrast to wearable technologies. In smart textiles, smart materials (e.g., piezoelectric) are formed into yarns that are woven into fabrics for clothing. One immediate requirement for such textiles is their stability during washing cycles, as expected of any clothing items, which has been largely lacking so far. Here, we investigate the washing stability of nanofibrous piezoelectric textiles. Our results reveal that electrospun textiles exhibit remarkable structural stability from the fiber microstructure to the textile level. Overall fiber crystalline composition and electroactive phase remain stable within 1% of ~47% and ~85%, respectively. Mechanically, the textile displays sustained performance, with only negligible changes observed. The yield strain and stress only show a ~8% and 9% differences, respectively. Moreover, piezoelectric stability is confirmed through phase preservation and slight variation in voltage output of ~6%. These results prove the candidacy that the processing of electrospun polyvinylidene fluoride (PVDF) fibers to woven textiles is applicable to the demands of smart textiles, which is expected to accelerate the commercialization of such textiles for wearable robotics and health monitoring.
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- Award ID(s):
- 2304785
- PAR ID:
- 10539562
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Applied Polymer Science
- ISSN:
- 0021-8995
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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