Autonomous Self-Healing, Antifreezing, and Transparent Conductive Elastomers

Abstract

It is a challenge to synthesize all-in-one molecular networks that are autonomously self-healable over a wide temperature range (from subzero to high), transparent, stretchable, and conductive. Here we demonstrate the fabrication of self-healing, transparent, conductive, and highly stretchable elastomers by a photoinitiated copolymerization of two polymerizable deep eutectic solvent (PDES) monomers, acrylic amide (AAm)/choline chloride (ChCl) and maleic acid (MA)/ChCl type PDESs. Hydrogen bonds between binary building blocks of the poly(AAm/ChCl-co-MA/ChCl) system can readily break and reform, allowing such all organic designed elastomers to self-heal over a wide temperature ranging from −23 to 60 °C while keep a highly transparent appearance. The hypermolecular network elastomers showed a fast self-healing property (within 2 s) without any other external stimuli and excellent self-healing efficiency (up to 94%). The elastomers were highly transparent (an average transmittance of 95.1%), intrinsically conductive (an ionic conductivity of 4.0 × 10–4 S cm–1), and stretchable (strains up to 450%) at room temperature. We hypothesize that this behavior will find their potential use in display and/or optically related fields of stretchable electronics in harsh environments.