Synthesis of 3D Hollow Layered Double Hydroxide-Molybdenum Disulfide Hybrid Materials and Their Application in Flame Retardant Thermoplastic Polyurethane

The development of high-performance thermoplastic polyurethane (TPU) with high flame retardancy and low toxicity has always been the focus of its research. In this paper, the novel 3D hollow layered double hydroxide/molybdenum disulfide (LDH/MoS(2)) hybrid materials were synthesized by hydrothermal method using the MIL-88A as in situ sacrificial template and MoS(2) as synergistic flame retardant. Among all TPU composites, the peak heat release rate, total heat release rate, and total smoke release rate of TPU/NiFeTb-LDH/MoS(2) were reduced by 50.9%, 18.2%, and 35.8% compared with pure TPU, respectively. The results of the thermogravimetric infrared analysis demonstrated that the contents of combustible volatiles (hydrocarbons) and toxic volatiles (CO and HCN) emitted from TPU/LDH/MoS(2) were significantly reduced, indicating that LDH/MoS(2) hybrid materials can dramatically enhance the fire safety of TPU composites. Combined with the analysis of carbon residues and thermal stability of TPU composites, the enhanced flame retardancy and smoke suppression performances are primarily attributed to the catalytic carbonization of LDH and the physical barrier effect of MoS(2).