Liquid Crystal Elastomers for Adaptive Intelligent Systems: From Molecular Design to Multifunctional Applications

Liquid crystal elastomers (LCEs), particularly nematic and cholesteric variants, have emerged as pivotal adaptive intelligent materials due to their unique capacity to reversibly translate microscopic molecular reorientation into macroscopic deformation and optical responses. This review provides a comprehensive overview of recent breakthroughs in LCE-based adaptive systems, systematically examining their fundamental stimulus-response mechanisms, network architecture engineering, advanced fabrication techniques, and cutting-edge applications. Special emphasis is placed on strategies for lowering actuation thresholds to near-ambient or body temperatures through chemical composition modulation, dynamic covalent adaptable networks, and innovative processing methods such as hybrid cooling 3D printing. We further highlight the integration of LCEs into multifunctional platforms for dynamic thermal management, multispectral camouflage, high-density information encryption, deformable energy storage, and closed-loop soft actuators with intrinsic sensing capabilities. Despite significant progress, challenges regarding large-scale manufacturing, long-term cyclic stability, and precise spatiotemporal control remain. By synthesizing current design principles and identifying critical technological bottlenecks, this review aims to guide the rational development of next-generation programmable, multifunctional, and environmentally resilient LCE systems, ultimately accelerating their transition from laboratory prototypes to real-world adaptive intelligent applications.