Conductive, self-healing, and repeatable graphene/carbon nanotube/polyurethane flexible sensor based on Diels-Alder chemothermal drive

Flexible conductive materials have excellent stretchability and sensitivity, so they have great development potential in motion detection, artificial electronic skin and other fields. Three-dimensional (3D) carbon nanomaterials are important materials for preparing flexible conductive polymers with good electrical conductivity. But its cost is too high to be widely promoted. In this paper, the modified graphene (FGO) and carbon nanotubes (FMCNTs) were prepared to three-dimensional structures to provide excellent electrical conductivity for the polymer. The reversible bond was introduced into the waterborne polyurethane by using Diels-Alder (DA) chemical crosslinking. Then the conductive and self-healing flexible electronic materials FGO/FMCNTs/WPU were prepared by penetration. The results showed that the composites had excellent thermal and mechanical properties. When the content of nanomaterial was 6 mg/ml, the stress was 9.58 MPa, the strain was 207, and the electrical conductivity was 0.0283 S/m. Nanomaterials also showed good self-healing ability because they had three-dimensional structures. The application test of the composite material showed that it could accurately monitor the human body motion. This indicated that the composite material can be used to manufacture flexible electronic devices.