Interfacial Molecular Engineering for Patternable and Stretchable Metal Electrodes

Intrinsically stretchable elastomers have emerged as promising platforms for wearable and reconfigurable electronics because of their excellent mechanical compliance. However, direct metal deposition on elastomeric substrates is often limited by weak interfacial adhesion, leading to crack formation, metal delamination, and severe electrical instability under repeated mechanical deformation. Here, we present an interfacial engineering strategy for patternable and stretchable metal electrodes based on polyethyleneimine (PEI)-functionalized styrene–ethylene–butylene–styrene-graft-maleic anhydride (SEBS-g-MA). Covalent grafting of PEI onto SEBS-g-MA creates an amine-rich interface that promotes strong interactions with deposited metal films, enabling robust metal adhesion while preserving the intrinsic elasticity of the elastomer. The engineered interface effectively suppresses crack propagation and interfacial delamination during tensile deformation, resulting in electrically stable metal electrodes under repeated stretching. Furthermore, the proposed platform supports direct deposition and arbitrary patterning of various metal films, providing a simple, scalable, and versatile approach for next-generation stretchable electronic systems, including wearable sensors, electronic skins, and soft bioelectronics.