Digital Light Processing (DLP) 3D printing enables the creation of hierarchical complex structures with specific micro‐ and macroscopic architectures that are impossible to achieve through traditional manufacturing methods. Here, this hierarchy is extended to the mesoscopic length scale for optimized devices that dissipate mechanical energy. A photocurable, thus DLP‐printable main‐chain liquid crystal elastomer (LCE) resin is reported and used to print a variety of complex, high‐resolution energy‐dissipative devices. Using compressive mechanical testing, the stress–strain responses of 3D‐printed LCE lattice structures are shown to have 12 times greater rate‐dependence and up to 27 times greater strain–energy dissipation compared to those printed from a commercially available photocurable elastomer resin. The reported behaviors of these structures provide further insight into the much‐overlooked energy‐dissipation properties of LCEs and can inspire the development of high‐energy‐absorbing device applications.
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.more » « less
- NSF-PAR ID:
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials
- Medium: X
- Sponsoring Org:
- National Science Foundation
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