Affiliation:
1. School of Chemistry and Chemical Engineering Guangdong Provincial Key Lab of Green Chemical Product Technology State Key Laboratory of Pulp and Paper Engineering South China University of Technology Guangzhou 510640 China
2. Department of Materials Science and Engineering Southern University of Science and Technology Shenzhen 518055 China
3. School of Chemical Engineering and Light Industry Guangdong University of Technology Guangzhou 510006 China
Abstract
AbstractGel‐based adhesives show promising prospects in epidermal bioelectronics because of their potential applications in physiological signal collection and electrical stimulation. An ideal epidermal adhesive should exhibit robust adhesion for lamination and poor adhesion for easy peeling, in addition to strain‐insensitivity in electrical properties for motion‐artifact‐free physiological signal collection. Here, lignosulfonate‐derived organohydrogel adhesives with anisotropic and tunable adhesion, together with unprecedented strain‐insensitivity are synthesized. The organohydrogel exhibits a high interfacial toughness of 728 J m−2 on fresh porcine skin, while the adhesion can be screened by covering a denatured silk fibroin. An anisotropic adhesive with an adhesion heterogeneity is designed, showing a 14.2‐fold difference in adhesion strength along two different directions for on‐demand attachment and removal. The adhesive can transform into a highly porous structure, which has only a 3% resistance increase at 100% strain. The strain‐insensitivity of the adhesive lies in the strong interaction of ions and the 3D porous structure, which enables motion‐artifact‐free and high‐quality electrophysiological signal collection within the strain range of the human skin. The lignosulfonate‐derived on‐demand organohydrogel adhesive is expected to be used in epidermal bioelectronics, human‐machine interaction, metaverse, and beyond.
Funder
National Natural Science Foundation of China
State Key Laboratory of Pulp and Paper Engineering