Electric‐Field Regulation of Adhesion/De‐Adhesion/Release Capacity of Transparent and Electrochromic Adhesive

Abstract

Abstract Removing adhesive nondestructively and intact from the adhered surface is a difficult challenge for advanced adhesive materials. Compared with the commonly used thermal or chemical release, the controlled adhesive release via electric‐field offers practical application advantages. However, a noninvasive release mode such as this has not been available for the de‐bonding of supramolecular adhesives that originate from small organic molecules. Herein, a conductive hydrogel with surface adhesion and electric field‐triggered de‐adhesion and release is fabricated from thioctic acid ( TA ) and L‐arginine ( LA ). The non‐covalent intermolecular attractions of poly[ TA ‐ LA ], especially its electrostatic interactions, not only endow it with useful bulk‐state properties and strong adhesion (up to 363.3 kPa) but also generate electric responsiveness for on‐demand de‐adhesion and release. The poly[ TA ‐ LA ] adhesive layer can be easily released within a short time (<60 s) under a mild voltage (5≈10 V). After a combined experimental and theoretical investigation, It is concluded that the adhesive‐layer morphological and mechanical changes, activated by a weak current (1.1≈3.2 mA), are responsible for the adhesion failure, which takes place primarily at the anode. Importantly, rapid electric release of poly[ TA ‐ LA ] is applicable at low temperatures (5 V, 60 s, −40 °C) or underwater (5 V, 60 s, 25 °C).