Graphene oxide-assisted hybrid assembled fireproof nanocoatings for exceptional flame-retardant and smoke-suppressant flexible polyurethane foam

Plagued by inherent flammability, fabricating a uniform dense protective coating compatible of flame retardancy and smoke suppression is one of the most feasible ways to decrease the fire risk of lightweight polymeric foams. However, effectively integrating synergistic fire protection and simple fabrication processes remains a great challenge for the poor flame retardancy of single component. Herein, a graphene oxide-assisted assembly strategy is proposed for fabricating organic-inorganic hybrid 2D nanocoating, which is compatible with a facile one-step flocculation coating process, showcasing superior flame retardancy and smoke suppression efficiency for polyurethane foam without deterioration of its mechanical performance. Due to the uniform hybridization nature of nanocoating and its highly synergistic radical scavenging, gaseous dilution, and physical barrier effects, the resulting foam can rapidly self-extinguish without melt dripping during vertical burning, while also simultaneously exhibits a high limited oxygen index value, low heat (-66.5 %) and smoke release (-69.5 %), exhibiting more effective in protection of foam compared to single component or simple physical blends, powerfully defending against fire attack. This facile GO-assisted hybrid strategy provides new insight for designing high-performance fireproof nanocoating with ubiquitous nanoparticles.