Direct Ionic Ink Writing on and Penetrating into Elastomer for Patternable, Waterproof, and Wear‐Resistant Ionic Circuits

Abstract The increasing need for ionic circuits has driven the demand for patterning methods with excellent wear resistance and ease of preparation. However, the traditional method of the circuits modified on the surface frequently suffers from wear and detachment during use. Herein, an interpenetrating network of poly(ionic liquid) and polyurethane is employed, creating a patternable ionic circuit that can resist the abrasion of sandpaper or taping. Hydrophobic ionic liquids are successfully polymerized inside the polyurethane to achieve a waterproof ionic circuit, simultaneously reducing the impact of environmental humidity. Additionally, this ionic circuit possesses the capability to perceive the multisignals of temperature, pressure, and pressing shapes with the assistance of artificial intelligence. The interpenetrating network provides a simple and practical solution for the fabrication of wear‐resistant and stable patterned ionic circuits.