Combustion and thermal degradation properties of flame-retardant TPU based on EMIMPF6

Ionic liquids have been highlighted as nonflammable, environmentally friendly, and suggested as possible solvents. Here, the application of one ionic liquid (1-butyl-3-methylimidazolium hexafluorophosphate, EMIMPF6) in thermoplastic polyurethanes (TPU) is studied with a focus on fire safety improvement. The impact of the composition on combustion- and thermal degradation-related properties is investigated for EMIMPF6 concentrations of additive (similar to 2 mass%). A large impact on the combustion and thermal degradation properties is found for TPU containing EMIMPF6. EMIMPF6 can catalyze TPU decomposing to form char residue layer at low temperature. Then, the good flame retardant and smoke suppression properties are obtained by introducing EMIMPF6 into TPU system.