Description:
Developing an all-biomass feedstock, simple process and low-cost way to achieve cotton fabric flame retardation is of great significance in civil, military and industrial fields. Herein, making use of layer-by-layer coating of protein extracted from fishery waste fish scales and phytic acid (PA) derived from plant seeds, a nitrogen-phosphorus flame-retardant coating was constructured on the surface of cotton fabrics via strong electrostatic attraction and hydrogen bonds. The flame retardant property of the coated cotton fabrics demonstrated a significant improvement with a limiting oxygen index of 31.1%, meeting the flame retardant requirements of commercial fire-protection suit. Besides, thermogravimetric and cone calorimetric results indicate that surface coating contributes to peak heat release rate and total smoke release, which are 49.2% and 139% lower, compared with pure cotton fabrics, respectively. Scanning electron microscopy and Raman results of the residual char further reveal the treatment of combined coating facilitates the formation of dense and regular graphitized char residue during combustion or under high temperature. This waste-sourced, biomass-derived coating paves the new way towards sustainable flame-retardant fabrics