Construction of durable flame retardant, anti-dripping, and smoke-suppressing recycled polyester fabric

Recycled poly(ethylene terephthalate) (R-PET) fabrics offer a sustainable and eco-friendly alternative to virgin PET but exhibit high flammability and increased smoke emission. In this study, magnesium hydroxide nanoparticles (nano-Mg(OH)2) with the particle size of 53 nm were synthesized and combined with cyclic phosphate ester through high-temperature and high-pressure immersion technology. The organic‒inorganic flame retardant (FR) agents were expected to penetrate the R-PET fibers, thus achieving high washing durability for flame retardancy and smoke suppression. The surface structural performance of nano-Mg(OH)2 and the smoke and heat suppression capacity, FR performance, mechanism and laundering resistance of the modified R-PET samples were also explored. The organic‒inorganic FR system significantly improved the FR properties and anti-dripping ability of R-PET while significantly reducing smoke and heat generation. Moreover, the modified R-PET fabrics exhibited self-extinguishing ability even after 40 washes, indicating their high washing resistance. The organic‒inorganic FR system was effective in both gas and condensed phase, providing multilevel fire safety. This study provides efficient and durable FR-functionalized R-PET fabrics with low smoke suppression and high fire safety.