Rewriting Polymer Fate via Chemomechanical Coupling

How can synthetic polymers be endowed with the continuous, life-like ability to grow, degrow, heal, and alter their chemical and physical properties after fabrication? This study addresses this question by coupling theory and experiment to create an open-system "living" polymer platform that integrates mass transport, reversible polymerization, chain exchange, and evolving elasticity into a fully chemomechanically coupled network. Controlled transport, reaction, and stresses enable continuous growth and degrowth with microscale control enabled by light-activated catalysts. Their chemical composition can be reprogrammed on demand, tuning modulus by up to two orders of magnitude to either stiffen or soften the material. These capabilities enable self-growable electronics, transformative soft robots, and on-site damage-regenerating devices, establishing a foundation for sustainable, endlessly reprogrammable polymers.