Mechanical and thermal properties of carbon-nanotube-reinforced self-healing polyurethanes

The study was conducted to synthesize self-healing polyurethanes (PUs) in the presence of multiwalled carbon nanotubes (CNTs). Measurements of the self-healing ability of PUs synthesized from N3300 isocyanate and polytetrahydrofuran with various contents of CNTs were taken. The mechanical and thermal properties were studied to analyse healing efficiency in experimentally damaged composite samples. The addition of CNTs results in a slight decrease in the self-healing efficiency of nanocomposites as compared to pure PUs. PU samples containing 40% content of soft segments self-healed much better than the samples with 50% content of soft segments. Functionalized carbon nanotubes CNT-OH due to presence of surface functional groups interact with PU chains, which results in an increase in the healing efficiency of mechanical strength and thermal conductivity of nanocomposites.