Flame retardancy of cotton and cotton/polyester fabrics treated by coating with polymer blends containing aluminum and phosphorus metals under the effect of gamma irradiation

•Radiation was used to impart flame retardancy to cotton and cotton/PET fabrics via surface coating.•Coatings formulations based on PVA/PLST blends loaded with aluminum (Al) and phosphorus (P) metals.•Treated fabrics were evaluated by crease recovery, thermal stability and mechanical measurements.•Both Al ad P metal proved to satisfy the highest flame retardancy with minimum weight lose percent. The main objective is to impart flame retardancy finishing to cotton and cotton/polyester fabrics. In this process, the fabrics were first treated by coating with poly(vinyl alcohol) (PVA)/plasticized starch (PLST) blends and then exposed to gamma irradiation. The treated fabrics were then loaded with aluminum sulphate [Al2(SO4)3] and monosodium dihydrophosphate (MSDP). The treated fabrics were characterized by the measurements of water absorption, crease recovery, surface morphology and tensile mechanical. Moreover, thermal stability of the treated fabrics was investigated by thermogravimetric analysis (TGA). The thermal stability was further investigated by determining the activation energy by two different methods based on Broido and the Horowitz–Metzger approximation equations. The results showed that the chemical and physical properties of the treated fabrics with PVA/PLST/metal composites were significantly improved. The flammability test in terms of time to catch fire (TF), time after glowing (TG) and weight left (WL) showed that the treated fabric and loaded with [Al2(SO4)3] and MSDP metals displayed improved flammability than untreated fabrics. In addition, the durability of the flame retardancy finished fabrics was evaluated by measuring the limiting oxygen index (LOI) after repeated washing cycles according a standard testing method. The results of durability test indicated that the fabrics treated with composites based on both [Al2(SO4)3] or MSDP metals proved to satisfy the flame retardancy with minimum weight lose percent.