B/N/P synergistic system for multifunctional flame-retardant cotton fabrics with thermal stability and fine physical...

The flammability of cotton fabrics limits their application in certain fields, making it necessary to impart flame-retardant properties to them. In this experiment, a multi-element synergistic flame retardant, PNBAPP, was developed by introducing B/N/P elements. After modification, the limiting oxygen index (LOI) of the cotton fabric increased from 18 % to 42.1 % (WG: 24.7 %), and the damage length in the vertical flammability test decreased from 30.0 cm to 6.5 cm. Even after 50 washing cycles, the LOI remained at 25.6 %. Conical calorimetry (CCT) and thermogravimetric analysis (TG) tests showed that it effectively reduced the heat release rate (PHRR) and total heat release (THR) of cotton fabrics during combustion. At 800 °C, the residual char content in a nitrogen atmosphere increased from 16.58 % to 33.45 %. This indicates that PNBAPP possesses excellent thermal stability and superior catalytic carbonization capability. Additionally, the modified cotton fabric exhibits good whiteness, physical properties, durability, and certain antibacterial properties.