Green flame-retardant coatings based on iron alginate for polyester fabrics: Thermal stability, flame retardancy and mechanical properties

Polyester (PET) fabrics are widely used in our daily life, but they burn and drip quickly when they encounter flames, and the dripping can cause secondary damage to human bodies. In this study, flame-retardant finishing of PET fabrics was performed by preparing alginate coatings modified with Fe3+. A simple dip-coating technique was used and sodium alginate solution was employed to submerge PET fabrics, after that the coatings were complexed with Fe3+ to endow the flame retardancy of PET fabrics. The micromorphology, mechanical properties, thermal stability, flame retardancy, and burning behaviors of the coated PET fabrics were analyzed. Coated PET fabrics had a limiting oxygen index value of 29%. The vertical flame test illustrated that PET/Iron alginate-2 exhibited excellent self-extinguishing behaviors, no drips appeared. The peak heat release rate of PET/Iron alginate-2 was reduced by 70.3%. In the warp directions, compared with the control, the tensile strength of coated PET textiles increased dramatically. In a word, it is a green method to improve the flame retardancy and anti-dripping of PET fabrics.