Liquid crystal elastomers (LCEs) are promising candidates for creating adaptive textile‐based devices that can actively and reversibly respond to the environment for sensing and communication. Despite recent advances in scalable manufacturing of LCE filaments for textile engineering, the actuation modes of various LCE filaments focus on contractual deformations. In this study, manufacture of polydomain LCE filaments with potential scalability by wet‐spinning is studied, followed by mechanical exploitation to program liquid crystal mesogen alignments, demonstrating both contractual and twisting actuation profiles. By plying these LCE filaments into yarns with different twist concentrations, yarn actuation, and mechanical performance is tuned. Yarns plied at 4 twists per cm can generate up to a seven‐fold increase in elastic modulus while maintaining 90% of actuation strain performance from their native filament. The contractual and twisting LCE filaments are then embroidered with varying stitch types to spatially program complex 2D‐to‐3D transformations in “inactive” fabrics. It is shown that a running stitch can actuate up to 15% in strain and create angular displacements in fabric with twisted mesogen alignments. It is envisioned that the wet‐spun polydomain LCE filaments for diverse plied yarn production together with textile engineering will open new opportunities to design smart textiles and soft robotics.
A liquid crystalline elastomer (LCE) network consisting of dynamic covalent bonds (DCBs) is referred as a LCE vitrimer. The mesogen alignment and the network topology can be reprogrammed locally in the LCE vitrimer by activating the bond exchange reactions using an external stimulus. After removal of the external stress, a new network is formed and the reprogrammed shape can be fixed, leading to a different set of the physical properties of the LCE vitrimers. Herein, this type of emerging materials is reviewed by a brief introduction of the fundamentals of LCEs, followed by discussions of various DCBs and the design principles for LCE vitrimers. After a presentation of different strategies to improve the stability and reprogrammability of the registered mesogen alignment, approaches to prepare LCE vitrimers with complex shapes and their actuations are discussed. Potential applications such as self‐healing and recycling, mechanochromic effects, and post‐functionalization of nanopores are also reviewed, followed by the conclusion of the remaining challenges and opportunities.
more » « less- PAR ID:
- 10430029
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Functional Materials
- Volume:
- 33
- Issue:
- 45
- ISSN:
- 1616-301X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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