A stretchable, self-healing conductive hydrogels based on nanocellulose supported graphene towards wearable monitoring of human motion

• Published in: Carbohydrate polymers Vol. 250; p. 116905
• Main Authors: Zheng, Chunxiao, Lu, Kaiyue, Lu, Ya, Zhu, Sailing, Yue, Yiying, Xu, Xinwu, Mei, Changtong, Xiao, Huining, Wu, Qinglin, Han, Jingquan
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 15.12.2020
• Subjects: Biocompatible Materials - chemistry; cellulose; cellulose nanofibers; compression strength; Electric Conductivity; electrical conductivity; electronics; free radicals; Graphene; Graphite - chemistry; Humans; Hydrogel; hydrogels; Hydrogels - chemistry; monitoring; Monitoring, Physiologic - instrumentation; Monitoring, Physiologic - methods; Movement; Nanocellulose; nanocomposites; Nanocomposites - chemistry; Polyacrylic acid; polymerization; robots; Self-healable; Sensing ability; storage modulus; tensile strength; viscoelasticity; Wearable Electronic Devices; Nanocellulose; Hydrogel; Sensing ability; Graphene; Polyacrylic acid; Self-healable
• ISSN: 0144-8617; 1879-1344; 1879-1344
• DOI: 10.1016/j.carbpol.2020.116905

[Display omitted] •A stretchable hydrogel is prepared by dispersing TOCNF-carried GN into PAA.•Mechanical toughness and electro-conductibility are enhanced by TOCNF-GN nanocomposites.•Hydrogel-based sensor shows high sensitivity and self-healing efficiency. Stretchable, self-healing and conductive hydrogels have attracted much attention for wearable strain sensors, which are highly required in health monitoring, human-machine interaction and robotics. However, the integration of high stretchability, self-healing capacity and enhanced mechanical performance into one single conductive hydrogel is still challenging. In this work, a type of stretchable, self-healing and conductive composite hydrogels are fabricated by uniformly dispersing TEMPO-oxidized cellulose nanofibers (TOCNFs)-graphene (GN) nanocomposites into polyacrylic acid (PAA) hydrogel through an in-situ free radical polymerization. The resulting hydrogels demonstrate a stretchability (∼850 %), viscoelasticity (storage modulus of 32 kPa), mechanical strength (compression strength of 2.54 MPa, tensile strength of 0.32 MPa), electrical conductivity (∼ 2.5 S m−1) and healing efficiency of 96.7 % within 12 h. The hydrogel-based strain sensor shows a high sensitivity with a gauge factor of 5.8, showing great potential in the field of self-healing wearable electronics.