3D-Printable Elastomers for Real-Time Autonomous Self-Healing in Soft Devices

Abstract

Photocurable self-healing elastomers are promising candidates for producing complex soft devices that can mend damage. However, the practicality of these materials is limited by reliance on external stimuli, custom synthesis, manual realignment, and multihour healing cycles. This paper introduces a tough 3D-printable hybrid acrylate/thiol-ene elastomer (prepared with commercially available precursors) that exhibits nearly instantaneous damage repair in the absence of external stimuli. This rapid, hydrogen bond-driven self-healing enables meaningful restoration of mechanical properties, including tensile strains up to 344% post-damage. Furthermore, structured herringbone grafts are showcased as a compelling strategy to enable cohesive failure away from healed interfaces, realizing up to 18× increases in toughness from only modest increases in interfacial surface area. Prototype soft robotic devices fabricated using vat photopolymerization demonstrate self-healing within seconds under ambient conditions and without external intervention. These results demonstrate a scalable strategy to provide real-time, autonomous functionality restoration in damaged soft devices.