Wearable electronics have become an important part of daily lives. However, its rapid development results in the problem of electronic waste (e‐waste). Consequently, recyclable materials suitable for wearable electronics are highly sought after. In this study, a conductive recyclable composite (PFBC) is designed based on a dynamic covalently cross‐linked elastomer and hierarchical hybrid nanofillers. The PFBC shows excellent wide‐ranging properties including processability, elasticity, conductivity, and stability, which are superior to previous materials used for recyclable electronics, and exhibits outstanding mechanical properties and environmental tolerance including high temperature, high humidity, brine, and ethanol owing to its covalent cross‐linking. Reversible dissociation of Diels–Alder networks allows for convenient processing and recycling. After three recycles, the toughness of the PFBC remained at 10.1 MJ m−3, which is conspicuous among the reported recyclable electronic materials. Three types of PFBC‐based wearable electronics including a triboelectric nanogenerator, a capacitive pressure sensor, and a flexible keyboard, are successfully 3D printed with excellent performance. The PFBC possessed both recyclability and degradability, the combination of which provides a new way to reduce e‐waste. This is the first work to recycle electronics using direct 3D printing and presents promising new design principles and materials for wearable electronics.

A dynamic oxime–carbamate based polyurethane hot melt adhesive was developed with outstanding adhesion performance to multiple substrates, and detachable and self-healing properties.

Natural tissues possess superior material properties such as self-healing, mechanical robustness, and mechanical gradients that allow organisms to adapt and survive in dangerous environments. Although highly desired, imparting synthetic materials with these biomimetic protective features remains a challenge. Here, the versatile dimethylglyoxime-urethane (DOU) moiety is used to create a multifunctional polyurethane (DOU-PU). The reactivities of DOU including reversible dissociation, metal coordination, photolysis enabled self-healing, high strength and toughness, mechanical gradient formation, and spatially controlled functionalization. By incorporating DOU, a multifunctional protective film is produced with superior resistance to mechanical damage, rapid room temperature self-healing, and anti-counterfeiting features. This super biomimetic film is expected to be very useful for the protection of various types of valuable objects such as electronics, diplomas, currency, and automobiles.

Actuators have shown great promise in many fields including soft robotics. Since reconfiguration allows actuators to change their actuation mode, it is considered a key characteristic for new‐generation adaptive actuators. However, it remains a challenge to design simple and universal methods to fabricate actuators that can be reconfigured to allow diverse actuation modes. Here, a macroscopically discretionary healing‐assembly strategy to fabricate reconfigurable soft actuators based on intrinsic self‐healing poly(dimethylglyoxime‐urethane) (PDOU) elastomers is developed. The PDOU elastomers with different degrees of crosslinking show different responsiveness to solvents, and are seamlessly healed. Crosslinked and non‐crosslinked PDOU elastomers as building units are healing‐assembled into actuators/robots with diverse actuation behaviors. Notably, the assembled actuators/robots are readily reprogrammed to exhibit multiple actuation modes by simply tailoring and reassembling without any external stimuli. This work paves a new, simple, powerful, and universal method to construct sophisticated soft robots.

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