Inter-fiber spacer-aided rawhide drying for skin-like and eco-friendly wearable platform of e-skin

Abstract

The next-generation on-skin devices are expected to provide identical textural characteristics to skin for accomplishing comfortable long-term wearability. Cattle hide is mainly consisted of type I collagen, which is therefore an ideal collagenous-matrix platform for developing skin-like on-skin devices. However, the raw cattle hide has a high water content that leads to poor wearability. Herein, we developed the skin-like wearable (SW) platform via a brand-new inter-fiber spacer-aided (IFS-aided) drying of cattle hide, where an amphiphilic nonionic surfactant that was capable of thoroughly infiltrating into the 3D hierarchical network of collagen fibers (CFs) was employed to work as the inter-fiber spacer to avoid the sticking of CFs during drying. Moreover, the inter-fiber spacer was easily eluted after drying for obtaining the collagenous matrix with highly dispersed fiber structure. The as-developed SW-platform exhibited ideal wearability by exhibiting full-protein nature, outstanding softness (6.808 mm), exceptional water-vapor permeability (5950 g·m^-2·d^-1) and high thermal stability. The hierarchical fiber structure with sufficient inter-fiber space endowed the SW-platform with reversible cross-scale deformations of CFs at both the nanoscale and microscale, which demonstrated its promising application in developing the skin-like and eco-friendly e-skins with outstanding sensing capability and flexible display function.

Graphical Abstract

Keywords

Inter-fiber spacer / Aided drying / Fiber sticking / Skin-like platforms / E-skins

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Funding

Joint Funds of the National Natural Science Foundation of China(No. U24A20545)

National Natural Science Foundation of China(No. 2217081161)

Program of Sichuan University Featured Research Groups in Engineering Disciplines(Program of Sichuan University Featured Research Groups in Engineering Disciplines)

RIGHTS & PERMISSIONS

The Author(s)