improving fire performance of thermoplastic polyurethane with an intumescent flame retardant system and nanomolybdenum disulfide

Today, nano fillers are used as flame retardant additives for polymers. among them, molybdenum disulfide (mos2) is used as an effective flame retardant in polymer composites due to low thermal conductivity and non-combustibility. in this study, a multicomponent halogen free flame retardant system consisting of 15 wt. % ammonium polyphosphate (app), 5 wt. % pentaerythritol (per), 5 wt. % melamine  polyphosphate (mpp) as intumescent flame retardant (ifr) with 1 wt. % nanomolybdenum disulfide was proposed to improve fire behavior of thermoplastic polyurethane (tpu). flammability properties were investigated using small scale ul 94 fire test and cone calorimeter. some key thermal and smoke parameters as well :as char: residue effect were discussed. based on the test results, the applied flame retardant, reduced the peak heat release rate (phrr) by 65.9% and total smoke release (tsr) by 31.1% compared with the original tpu. moreover, the tpu nanocomposite reached v-0 class in the ul 94 test. the char residue after cone calorimeter test increased by 75.9% indicating the efficiency of the applied flame retardants leading to improvement of fire performance.