Self‐Healing, Recyclable, Biodegradable, Electrically Conductive Vitrimer Coating for Soft Robotics

Abstract

Sensors and transducers enable the robots’ movements and interactions with humans and the environment. Particularly, tactile and motion sensors, even those inspired by the human skin, often miss many of its essential features. Indeed, the materials that constitute such sensors are often rigid and lack self‐healing and biodegradability. Furthermore, the large‐scale diffusion of these technologies propelled by robots spread in many aspects of the lives, from industrial to household settings, contributes heavily to the electronic and robotic waste problem. Recycling strategies for materials for robotics sensors are thus pivotal for future development. This work proposes self‐healable, recyclable, and biodegradable electrically conductive coatings. These coatings are based on conductive inks that combine graphene nanoplatelets and carbon nanofibers with a soft biodegradable vitrimer binder and are realized by spray coating. The use of the vitrimer ensures satisfying adhesion to diverse substrates, flexibility, conformability, self‐healing, and recyclability of the conductive coating. This material is a sustainable alternative to standard conductive inks for flexible electronics and soft robotics. Indeed, tests for the live monitoring of SoftHand3, the grasping system of many worldwide diffused robots, have yielded promising results. The use of biodegradable ingredients and the possibility of recycling makes it an appealing material to face the sustainability issue of today's electronics and robotics.