Self-Healing Composite Polymers Based on Spin Crossover Materials for Multidirectional Preprogrammed Actuation

A dimethylglyoxime–urethane-based self-healing polyurethane elastomer with a distinct two-phase morphology combining high extensibility (>500%), a high Young's modulus (40 MPa), and a high healing efficiency based on dual dynamic bonds at room temperature was obtained. Such a polymer was used for fabrication by blade casting and/or self-healing bilayer actuators incorporating a composite layer formed by anisometric spin crossover particles presenting anisotropic volume change and showing large transformation strain above room temperature. Thus, the self-healing polymer, generally used for damage reparation, is also useful for the shaping of the bilayer composite actuator as well as to guide its preprogrammed motion.