Arbitrarily 3D Configurable Hygroscopic Robots with a Covalent-Noncovalent Interpenetrating Network and Self-Healing...

Soft materials that can reversibly transform shape in response to moisture have applications in diverse areas such as soft robotics and biomedicine. However, the design of a structurally transformable or mechanically self-healing version of such a humidity-responsive material, which can arbitrarily change shape and reconfigure its 3D structures remains challenging. Here, by drawing inspiration from a covalent-noncovalent network, an elaborately designed biopolyester is developed that features a simple hygroscopic actuation mechanism, straightforward manufacturability at low ambient temperature (≤35 °C), fast and stable response, robust mechanical properties, and excellent self-healing ability. Diverse functions derived from various 3D shapes that can grasp, swing, close-open, lift, or transport an object are further demonstrated. This strategy of easy-to-process 3D structured self-healing actuators is expected to combine with other actuation mechanisms to extend new possibilities in diverse practical applications.