Biomass phytate salt-based flame-retardant polyurethane coating for outdoor polyester fabric: a long-lasting solution

Polyurethane (PU)-coated polyester fabrics are commonly used in outdoor settings, but their flame-retardant properties are somewhat lacking. In this study, biomass phytate salt was applied to improve the flame retardancy and anti-dripping properties of PU-coated polyester fabrics. This study also explored the hydrostatic pressure, mechanical performance, heat release capacity, flame retardancy, washing durability, and mode of action of coated polyester fabrics. The polyester fabric coated with 4% phytate salt-modified PU exhibited impressive self-extinguishing properties without any dripping. Additionally, the coated polyester fabric showed a low damaged length of 12.2 cm and a high LOI of 33.8%, satisfying the requirements for the B1 level. The coated polyester fabric proved to withstand 50 washing cycles, highlighting its remarkable flame retardancy efficiency and durability. It also exhibited a significant reduction in heat release, suggesting the fire safety performance. Analysis of the thermal resistance and char residue revealed a condensed flame-retardant mechanism attributed to the phytate-based system. Overall, phytate salt shows promising potential as a long-lasting flame-retardant system for outdoor PU-coated polyester fabrics.