Autonomous self-healing 3D micro-suction adhesives for multi-layered amphibious soft skin electronics

Autonomously self-healing, reversible, and soft adhesive microarchitectures and structured electric elements could be important features in stable and versatile bioelectronic devices adhere to complex surfaces of the human body (rough, dry, wet, and vulnerable). In this study, we propose an autonomous self-healing multi-layered adhesive patch inspired by the octopus, which possess self-healing and robust adhesion properties in dry/underwater conditions. To implement autonomously self-healing octopus-inspired architectures, a dynamic polymer reflow model based on structural and material design suggests criteria for three-dimensional patterning self-healing elastomers. In addition, self-healing multi-layered microstructures with different moduli endows efficient self-healing ability, human-friendly reversible bio-adhesion, and stable mechanical deformability. Through programmed molecular behavior of microlevel hybrid multiscale architectures, the bioinspired adhesive patch exhibited robust adhesion against rough skin surface under both dry and underwater conditions while enabling autonomous adhesion restoring performance after damaged (over 95% healing efficiency under both conditions for 24 h at 30°C). Finally, we developed a self-healing skin-mountable adhesive electronics with repeated attachment and minimal skin irritation by laminating thin gold electrodes on octopus-like structures. Based on the robust adhesion and intimate contact with skin, we successfully obtained reliable measurements during dynamic motion under dry, wet, and damaged conditions.