NIR-induced scratch self-healing properties of waterborne polyurethane/polypyrrole nanocomposites

High temperature can cause aging of materials , so it is urgent to investigate self-healing materials with low temperature positioning and self-healing ability. In this paper, water-based polyurethane/polypyrrole nanocomposites with NIR-induced self-healing properties (SWPUA/PPy) were prepared by mixing polypyrrole nanoparticles (PPy) as photo-thermal conversion agent with self-healing waterborne polyurethane emulsion (SWPUA). The effects of PPy content on thermal stability, mechanical properties and self-healing effects of SWPUA/PPy nanocomposites were investigated. The results showed that the addition of PPy had little effect on the chemical structure of SWPUA, and a small amount of PPy could make the material have excellent NIR-induced self-healing properties. When PPy content was 0.0125 wt %, the self-healing efficiency of NIR irradiation for 40 min was 89.25 %. Besides, the addition of PPy also improved the thermal stability and tensile strength of SWPUA/PPy samples.