Photothermal‐Responsive Lignin‐Based Liquid Crystalline Elastomers: Constructing High‐Performance Artificial Muscles via a Dual Dynamic Network

ABSTRACT The development of smart actuators that integrate robust mechanical properties with rapid responsiveness remains a critical challenge for advancing artificial muscles. To address this, this study incorporates lignin—a renewable resource—into liquid crystalline elastomer (LCE) to fabricate a high‐performance photothermal‐responsive artificial muscle material. By leveraging the inherent aromatic conjugated structure of lignin as an efficient photothermal unit, we successfully integrated it with mesogens to construct a liquid crystalline network featuring a nanoscale microphase‐separated architecture. This network incorporates lignin‐based phenolic carbamate bonds and disulfide bonds concurrently, forming a dual dynamic crosslinking architecture that significantly enhances the mechanical properties of LCE, achieving a tensile strength of 21.5 MPa and an elongation at break exceeding 754%, thereby substantially surpassing conventional single‐network LCEs. It also confers outstanding photothermal response, enabling rapid, self‐actuated reversible deformation (33% strain). As a light‐driven artificial muscle, it achieves 40% reversible strain and 30.0 kJ/m 3 output power density. This work presents a novel strategy for developing high‐performance light‐driven LCEs through the integration of biomass lignin as both a reinforcing phase and an intrinsic photothermal converter. This approach not only enhances the material's performance but also offers promising pathways for the design and fabrication of next‐generation soft robots and artificial muscles.