Shape-memory-assisted self-healing of macroscopic punctures via high-energy-density periodic dynamic polymers with tunable actuation temperature

Shape memory polymers (SMPs) show promise in areas like wearable electronics and soft robotics but often have low (actuation) energy densities (<1 MJ/m3), limiting their maximum load. Recent work suggests that periodically incorporating directional H-bonds can enable high-energy-density SMPs by forming stable strain-induced supramolecular nanostructures. Here, we found that adding weaker H-bonding units to the polymer can tune its actuation temperature from 60°C to 25°C while maintaining ∼80% of the energy density of the original polymer and achieving self-healing at accessible temperatures (∼70°C). By using this self-healable, high-energy SMP, we realized rapid healing of macroscopic film damage (e.g., centimeter-sized knife punctures) that was not healable in polymers without high-energy shape-memory-assisted self-healing (SMASH) behavior. The self-healing SMP was used to fabricate a self-healable force sensor with high cyclability and sensitivity, marking a significant advancement in creating tunable and self-healable SMPs for smart, durable wearable devices.