Ionic liquid-modified MXene quantum dots imparting self-healing and antibacterial properties to commercial polyurethane

The simultaneous integration of self-healing capabilities and exceptional mechanical properties in materials remains a significant challenge in research. This study proposes a novel approach to address this issue by imparting self-healing functionality to commercial polyurethane without compromising its inherent mechanical strength. Ionic liquids were electrostatically adsorbed onto the surface of MXene quantum dots, triggering their reaction to form poly (ionic liquid)-coated MXene (MQDs@IL). These MQDs@IL were incorporated into commercial polyurethane, where hydrogen bonding interactions between the poly (ionic liquid) and the molecular chains in polyurethane, along with dynamically reversible ionic aggregates, facilitated molecular chain rearrangement. As a result, the modified polyurethane demonstrated an impressive self-healing efficiency of up to 80%. Additionally, the composite material exhibited enhanced mechanical properties, including increases in fracture strength and elongation at break by 9% and 14%, respectively, achieving a toughness of 294 MJ/m³. Furthermore, the modified polyurethane showed significant improvements in thermal stability and flame retardancy, alongside effective antibacterial properties against Escherichia coli and Staphylococcus aureus. These advancements not only extend the application range and service life of commercial polyurethane but also provide a promising strategy for the development of multifunctional self-healing materials.