Fabrication of phosphazene based covalent triazine polymer with excellent flame retardancy and smoke suppression for thermoplastic polyurethane

This short article mainly peruses smoke suppression properties and synergistic flame retardant effect of phosphazene and triazine rings on fire safty of thermoplastic polyurethane (TPU) composites using DAPT-HCCP COF as a flame retardant agent. The fire retardant properties of DAPT-HCCP COF on TPU matrix were intensively investigated by different analyses such as, thermalgravimetric analysis (TGA) and cone calorimeter test (CCT). Remarkably, the CCT data reveal that DAPT-HCCP COF effectively decrease the amount of smoke production during the combustion process. This, also can apparently reduce peak heat release rate (PHRR), total heat release (THR), and total smoke release (TSR) from about 1066 kW m−2, 77 MJ m−2, and 0.034 g s−1 for neat TPU to 588 kW m−2, 30 MJ m−2, 0.025 g s−1 for TPU/DAPT-HCCP 3 wt.% composite, respectively. Here, DAPT-HCCP COF is considered as a good smoke suppression agent having a synergistic effect between nitrogen and phosphorus elements in the flame retardancy of TPU. DAPT-HCCP COF can greatly improve the residual char structure, which is confirmed by TGA results.