Constructing a bio-based flame retardant coating through co-depositing polydopamine and guanosine 5′-monophosphate disodium salt (GMP) for flexible polyurethane foam

The fire hazard posed by the inherent flammability and smoke toxicity of flexible polyurethane foam (FPUF) often necessitates the incorporation of flame retardants to meet stringent regulations. The development of environmentally friendly strategies to enhance the fire resistance of FPUF is of increasing importance and a significant amount of research has been devoted to this end. In this work, a bio-based coating was constructed by co-depositing polydopamine and guanosine 5′-monophosphate disodium salt (GMP) to increase the fire safety of FPUF. The coating significantly improved the flame retardancy of FPUF. The FPUF@PDA-GMP samples showed an LOI value of 24.5% with a self-extinguishing effect and exhibited reduced release of heat, smoke, CO, CO2, and HCN due to their compact and strong char. The compressive strength at 70% strain of FPUF@PDA-GMP was 8 times higher than that of the control FPUF sample. The coating had a little negative effect on the resilience and improved its elongation at break. This investigation has provided a useful method for designing and producing high-performance foams.