A rare‐earth‐based nano‐flame retardant with 2D MXene for improving fire safety and mechanical property of thermoplastic polyurethane composites

AbstractA kind of rare earth flame retardant, two‐dimensional lamellar compounds (MXene) loading with cerium phosphate nanorod, MXene@CePO4 (CMX) was prepared by hydrothermal and electrostatic adsorption methods. It was then applied in thermoplastic polyurethane (TPU). With the 3 wt% addition of CMX improving the mass rate of residual char from 4.42 wt% to 11.33 wt% compared to pristine TPU, there were reductions of 53.8%, 12.3%, and 24.7% in peak heat release rate (pHRR), total heat release (THR), and smoke density maximum (Ds max), respectively. Moreover, the TPU/CMX composites were shown to have superior mechanical properties compared with pristine TPU. For TPU/CMX‐3.0, there was a visible improvement in tensile strength (TS) and elongation at break (EB) of 12.5% and 54.1% respectively, compared to pure TPU. The analysis of the flame retardancy mechanism of TPU/CMX shows that CMX plays an effective role in quenching free radicals in the gas phase and promotes char formation of TPU in the condense phase. Therefore, this paper offers a new solution for designing multifunctional rare earth flame retardants that are applied in TPU, thereby extending its application in industries and daily life.