Tunable photo-responsive liquid crystal elastomer fibers <i>via</i> disperse dyeing for smart textiles

Active fibers, responding autonomously to environmental changes, are the basis of the development of smart textiles. However, there are still challenges in achieving responsive specificity and self-resilience of these fibers, which restrict the implementation of precise and complex actuation behaviors. Herein, an efficient strategy with a combination of a two-step crosslinking and disperse dyeing method was proposed to integrate multiple independent and non-interfering photo-thermal conversion nanoparticles into liquid crystal elastomer fibers (LCEFs). Three dyed LCEFs that selectively respond to 532 nm, 808 nm, and 980 nm wavelengths of light have been achieved. Based on this, a Delta robot was constructed with the capability of identifying specific light. The dyed LCEFs were also successfully incorporated into functional textiles through different fabrication technologies, demonstrating an embroidered anti-counterfeit logo, a 2D to 3D transformable disc-woven bionic flower, and an adaptive breathing knitted fabric. This work may facilitate the development of untethered soft robots with tunable and complex actuation, as well as the advancement of novel smart fabrics.