Orthogonal light triggering of dynamic polymer networks toward on-demand shape evolution control

Shape-shifting materials are bases of soft machines to accomplish sophisticated tasks. While significant progress has been made in diversifying shape transformation behaviors, current evolution pathways are determined by pre-programming approaches, limiting real-time adaptability and flexibility during operation. Here, we report a dynamic covalent polymer network swollen with a nonvolatile aliphatic acid mixture, which enables multi-shape memory properties. During shape-shifting, ultraviolet light is employed to spatially lock the geometries through disulfide bond exchange, allowing the on-demand adjustment of shape evolution. Additionally, the introduction of a photothermal azobenzene derivative allows the gel to undergo sequential shape recovery upon near-infrared light irradiation. This design facilitates real-time control of shape evolution through orthogonal light, overcoming the constraints of pre-programming. Building on this, the polymer is employed as a functional switch with an error-correction capability to enhance electrical safety. The versatility and adaptability of our strategy exhibit great potentials to fabricate future shape-shifting devices.