Abstract: In this study, a P/N synthesized flame retardant, POC, was prepared by reacting collagen with phosphenylic acid (PPOA), and used to improve the flame retardancy of polyester cotton blended fabrics (PTCO) by the dip‒drying method. A detailed study was conducted on the microstructure, thermal stability, flame retardancy, combustion behavior, mechanical properties, antibacterial properties, and flame‒retardant mechanism of finished PTCO. The scanning electron microscope images indicated that POC was uniformly deposited on the surface of PTCO. The Rmax of PTCO/POC under air atmosphere decreased by 20.3%, and the char residues at 700 ℃ increased from 0.6% to 3.3%. PTCO/POC can self‒extinguish, with an afterflame time and afterglow time of 0 s, a damaged length of 7.8 cm, and an LOI value of 28.2%. In cone calorimeter test, the time to ignition was extended from 26 s to 35 s, and the peak heat release rate and total heat release values were decreased by 33.8% and 23.6%, respectively. In addition, the breaking force of PTCO/POC was increased from 725 N of PTCO/PPOA to 810 N, remaining 88.1% of the breaking force compared with that of PTCO. The antibacterial rates of PTCO/POC against Escherichia coli and Staphylococcus aureus both reached 99.99%. In summary, PTCO/POC owned better flame retardancy and antibacterial properties.

Key words: polyester cotton blended fabrics, flame retardancy, antibacterial property, tensile strength