Skin-inspired hydrogel–elastomer hybrids with robust interfaces and functional microstructures

TLDR

Soft hydrogel–elastomer hybrids inspired by mammalian skin promise applications in stretchable electronics, microfluidics, tissue engineering, soft robotics, and biomedical devices, yet current versions suffer from weak interfaces, low robustness, and difficulty patterning microstructures. The study presents a simple, versatile method to assemble hydrogels and elastomers into hybrids with extremely robust interfaces and functional microstructures such as microfluidic channels and electrical circuits. The method applies to a range of tough hydrogels and common elastomers such as PDMS Sylgard 184, polyurethane, latex, VHB, and Ecoflex. The hybrids enable anti‑dehydration materials, stretchable and reactive microfluidics, and stretchable hydrogel circuit boards patterned on elastomer.

Abstract

Abstract Inspired by mammalian skins, soft hybrids integrating the merits of elastomers and hydrogels have potential applications in diverse areas including stretchable and bio-integrated electronics, microfluidics, tissue engineering, soft robotics and biomedical devices. However, existing hydrogel–elastomer hybrids have limitations such as weak interfacial bonding, low robustness and difficulties in patterning microstructures. Here, we report a simple yet versatile method to assemble hydrogels and elastomers into hybrids with extremely robust interfaces (interfacial toughness over 1,000 Jm −2 ) and functional microstructures such as microfluidic channels and electrical circuits. The proposed method is generally applicable to various types of tough hydrogels and diverse commonly used elastomers including polydimethylsiloxane Sylgard 184, polyurethane, latex, VHB and Ecoflex. We further demonstrate applications enabled by the robust and microstructured hydrogel–elastomer hybrids including anti-dehydration hydrogel–elastomer hybrids, stretchable and reactive hydrogel–elastomer microfluidics, and stretchable hydrogel circuit boards patterned on elastomer.