Dynamic covalent polyurethane surface activation enabled stretchable, tough-adhesive, and conductive interface for soft/rigid hybrid electronics

The development of reliable stretchable hybrid electronics (SHEs) requires the formation of soft/rigid interfaces that simultaneously achieve low electrical impedance, robust mechanical-electrical bonding and high energy dissipation capacity, which remains a critical challenge at present. In this work, an innovative alcohol vapor activation for dynamic covalent polyurethane elastomers was presented to address this problem. Specifically, through competitive intervene in the dynamic exchange of hindered urea bonds, ethanol forms irreversible polar urethane terminals, enabling precise surface polarity tuning and enhanced self-adhesion (peel strength of 2.04 N cm^-1) without compromising bulk mechanical properties. This activated surface facilitates significant improvements including high conductivity (8 Ω sq^-1) through rapid nanofiller embedding; direct integration of rigid components with durable interfaces; exceptional electromechanical stability (resistance change less than 10% during bending, twisting, and stretching). The prepared SHEs demonstrate significant potential for applications in stretchable circuits, wearable control terminals, and healthcare monitoring systems.