Preparation of carbon nanotube-vitrimer composites based on double dynamic covalent bonds: Electrical conductivity, reprocessability, degradability and photo-welding

Emerging as an innovative class of polymeric material, vitrimers possess the advantages of thermoplastics as well as thermosets and of great interest due to its ability to reduce environmental pollution and waste of resources caused by plastic abuse. In the present work, we prepared a series of carbon nanotube-vitrimer composites (EPCNT_x) containing double dynamic covalent bonds (carboxylate and disulfide bonds), of which EPCNT₅ (the MWCNTs content is 5 wt%) displayed the best electrical conductivity (1.63 S/m) and good mechanical properties (tensile stress = 16.3 MPa, fracture strain = 81.8%). Additionally, EPCNT₅ has the advantages of vitrimer, i.e., reprocessability, degradability, and photo-welding performance, fully combining the advantages of vitrimer and epoxy composites. Furthermore, the EPCNT₅ is fabricated as a skin sensor, demonstrating its potential application in the field of skin sensing.