Document Type
Conference Paper
Publication Date
10-6-2026
Abstract
The rapid evolution of soft robotics, wearable diagnostics, and bio-compatible electronic devices has intensified the demand for resilient, highly deformable materials with the capability to mimic soft biological tissues (skin, organs). A persistent bottleneck in the development of next-generation soft machines is the compliance mismatch at interfaces between conventional, rigid electronic components and soft elastomeric substrates. This disparity in mechanical moduli generates localized strain concentrations during device deformation that can result in delamination, material fatigue, and overall device failure. Although multimaterial or layer-by-layer architectures have been explored to bridge this gap, traditional fabrication methods typically rely on complex manufacturing protocols, suffer from poor interfacial adhesion, and lack damage-mitigation strategies after damage onset.
Self-healing elastomers (SHEs), which offer the potential for repair and extended device lifetimes, are promising candidates for addressing these challenges. In this work, we introduce a material library built on a previously reported 3D-printable SHE. Produced utilizing commercial off-the-shelf (COTS) precursors, this material system undergoes rapid, hydrogen bond-driven, intrinsic self-healing under room-temperature conditions and requires no external thermal or chemical stimulus to activate damage repair. Through selective adjustment of precursor stoichiometry — in particular, by varying the ratio of a four-arm thiol chain-transfer agent, pentaerythritol tetrakis(3-mercaptopropionate) (PETMP) to 1,6-hexanediol diacrylate (HDDA) within a 2-hydroxyethyl acrylate (HEA) monomer matrix — we establish a broad mechanical property design space from a single SHE material system.
Leveraging this design space, we demonstrate both discrete assembly and continuous digital light processing (DLP) 3D printing of soft–hard substrates to eliminate soft–hard interfacial boundaries between rigid electrical components and deformable substrates. Adjusting the resin composition in situ during the printing process yields continuous substrates with a unidirectional stiffness gradient. This approach positions mechanically rigid formulations as mounting locations for rigid payloads, while ultra-stretchable formulations isolate strain away from sensitive circuits and components. Finally, the integration of stretchable conductive pathways onto these substrates is demonstrated through deposition of a commercially available, polymerized Ga-In liquid metal ink, establishing a scalable, easily manufacturable, tunable, self-healing material system that offers a promising pathway toward damage-resistant soft machines and stretchable electronic devices.
Keywords
Soft Robotics, Stretchable Electronics, Self-healing Elastomers, Mechanical Mismatch
Disciplines
Materials Science and Engineering | Mechanical Engineering
eCommons Citation
Burkhardt, Alex, "Toward Mechanical Mismatch Mitigation Enabled by Self-Healing Materials: A Review" (2026). Research from the Berry Summer Thesis Institute, 2026. 7.
https://ecommons.udayton.edu/uhp_bsti_2026/7
