3D-Printed ferromagnetic Liquid Crystal Elastomer with Programmed Dual-Anisotropy And Multi-Responsiveness.

Liquid crystal elastomers (LCE) and magnetic soft materials are promising active materials in many emerging fields, such as soft robotics. Despite the high demand for developing active materials that combine the advantages of LCE and magnetic actuation, the lack of independent programming of the LCE nematic order and magnetization in a single material still hinders the desired multi-responsiveness. In this study, we developed a ferromagnetic LCE (magLCE) ink with nematic order and magnetization that can be independently programmed to be anisotropic, referred to as dual anisotropy, via a customized 3D printing platform. The magLCE ink was fabricated by dispersing ferromagnetic micro-particles in the LCE matrix, and a 3D printing platform was created by integrating a magnet with 3-DoF motion into an extrusion-based 3D printer. In addition to magnetic fields, magLCEs can also be actuated by heating sources (either environmental heating or photo-heating of the embedded ferromagnetic microparticles) with a high energy density and tunable actuation temperature. We demonstrated a programmed magLCE strip robot with enhanced adaptability to complex environments (different terrains, magnetic fields, and temperatures) using a multi-actuation strategy. The magLCE also has potential applications in mechanical memory, as demonstrated by the multi-stable mechanical metastructure array with remote writability and stable memory. This article is protected by copyright. All rights reserved.