Mechanical and electrical properties of a modified carbon nanotube-mediated hydrogel as a strain sensor

Abstract

This study adopted a one-pot method to prepare a composite solution, which uses Polyvinyl Alcohol (PVA) as the matrix, silanation-modified carbon nanotubes (S-CNTs) as the conductive mediators, dimethyl sulfoxide (DMSO) aqueous solution and glycerol as the organic solvent, and finally the composite solution was repeatedly freeze-thawed to prepare a composite hydrogel. By controlling the addition amount of S-CNTs, its effect on the properties of the composite hydrogels was investigated. The microstructure, mechanical properties, and electrical properties of the composite hydrogel were characterized and the results showed that the S-CNTs-0.3/PVA hydrogel had good mechanical properties (tensile strength: 0.53 MPa, tensile modulus: 410 kPa, toughness: 0.97 MJ m⁻³ and elongation at break: 294.81%) and excellent self-recovery performance. The assembled sensor can monitor finger bending and strain occurrence, indicating its potential application in human motion monitoring energy-sensing devices.