Preparation of a Novel Yttrium‐Based <scp>MOF</scp> Containing Phosphazene Rings and Its Application in <scp>EP</scp>

ABSTRACT This paper developed a rare‐earth metal–organic framework (MOF) flame retardant and applied it to epoxy resin (EP). This process utilized hexa (4‐carboxyphenoxy) cyclotriphosphazene as the organic ligand and yttrium nitrate hexahydrate as the rare‐earth metal source to prepare a novel Yttrium‐based MOF (Y‐MOF) via a solvothermal method. The Y‐MOF synthesized under optimal conditions was characterized using scanning electron microscopy (SEM) and Fourier‐transform infrared spectroscopy (FT‐IR). Thermogravimetric Analysis (TGA) and cone calorimetry (CCT) results indicate EP‐1 exhibits excellent thermal stability with a high char residue of 12.25%. Concurrently, EP‐1 reduces peak heat release rate (PHRR) and total heat release (THR) by 51.56% and 26.23%, respectively. Total smoke production (TSP) decreased by 10.23%, while peak CO production rate (PCOP) and peak CO 2 production rate (PCO 2 P) decreased by 55.26% and 55.43%, respectively. The tensile strength and impact strength are 3.49% and 19.32% higher than those of pure EP, respectively.