Cellulose-based liquid crystal elastomer with tunable mechanochromic Response

The development of sustainable, high-performance elastomers with multifunctional capabilities is pivotal for the next-generation of eco-friendly technologies. Here, we overcome the intrinsic rigidity of cellulose, by orchestrating its molecular chains into dynamic, chiral-nematic ordered liquid crystal elastomers using hydroxypropyl cellulose. Precise control over elasticity and optical properties was achieved via a salt-induced Hofmeister effect, which modulates the interchain hydrogen-bond network. This network acts as a reversible softness regulator, while the embedded right-handed helical structures produce vivid, stimuli-responsive structural colors. Crucially, mechanical strain unwinds the helix in liquid crystal elastomer, resulting in a real-time, naked-eye mechanochromic response that directly visualizes the local stress. This dynamic color change enables real-time monitoring of mechanical stress for practical applications in rehabilitation training. Moreover, owing to the biocompatibility and biodegradability nature of cellulose, the obtained elastomer can be completely degraded within 30 days in soil. This work provides a scalable design route for sustainable elastomers that simultaneously offer high performance, multifunctionality, and embodied intelligence, paving the way for a distinct class of smart eco-friendly materials.