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Abstract Liquid crystal elastomers (LCE) are appealing candidates among active materials for 4D printing, due to their reversible, programmable and rapid actuation capabilities. Recent progress has been made on direct ink writing (DIW) or Digital Light Processing (DLP) to print LCEs with certain actuation. However, it remains a challenge to achieve complicated structures, such as spatial lattices with large actuation, due to the limitation of printing LCEs on the build platform or the previous layer. Herein, a novel method to 4D print freestanding LCEs on‐the‐fly by using laser‐assisted DIW with an actuation strain up to −40% is proposed. This process is further hybridized with the DLP method for optional structural or removable supports to create active 3D architectures in a one‐step additive process. Various objects, including hybrid active lattices, active tensegrity, an actuator with tunable stability, and 3D spatial LCE lattices, can be additively fabricated. The combination of DIW‐printed functionally freestanding LCEs with the DLP‐printed supporting structures thus provides new design freedom and fabrication capability for applications including soft robotics, smart structures, active metamaterials, and smart wearable devices.
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High‐Speed and Scalable Wet Spinning of Graphene/Liquid Crystalline Elastomer Composite Filaments
Abstract Liquid crystalline elastomers (LCEs) are promising candidates for the development of soft, environmentally‐responsive actuators and have recently been explored for application in smart textiles and soft robotics. To realize the potential of LCEs within these systems, the fast, scalable, and continuous production of LCE filaments at controlled diameters is critical. Here, a wet‐spinning method is presented for the scalable manufacturing of graphene/LCE composite filaments. Through a double diffusion mechanism, the graphene/LCE precursors rapidly crosslink into tangible filaments without the use of UV light, instead taking advantage of solvent exchange and high catalyst influx. The continuous production of polydomain graphene/LCE filaments can achieve speeds up to 4500 m h−1. Through π−π interactions between graphene and the LCE matrix, the composite graphene/LCE filaments across a broad range of diameters (137 to 1128 µm) can be obtained with high integrity, achieving actuation stresses and strains up to 3.66 MPa and 44%, respectively, in 3 s. The filaments are showcased as artificial muscles, where both thin and thick filament sizes are of interest. The presented scalable wet‐spinning method will open new opportunities to design smart textiles and soft robotics from fibers of controlled sizes.
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- Award ID(s):
- 2037097
- PAR ID:
- 10610822
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Functional Materials
- Volume:
- 35
- Issue:
- 24
- ISSN:
- 1616-301X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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