Two‐Dimensional Metal–Organic Framework Based Ternary Synergistic Flame Retardant System for Enhanced Fire Safety and UV Resistance of Ethylene‐Vinyl Acetate

ABSTRACT The high flammability of ethylene‐vinyl acetate (EVA) copolymers limits their important applications in fire safety, thus it has become imperative to improve the fire retardancy through the incorporation of flame retardants. In this study, a novel two‐dimensional (2D) metal–organic frameworks (MOFs) material of ZIF‐L has been successfully synthesized and characterized. An intumescent flame retardant (IFR) composed of ammonium polyphosphate (APP) and tannic acid (TA) in conjunction with ZIF‐L was constructed and molten‐compounded into the EVA matrix. The flame retardancy of EVA composites was evaluated using limiting oxygen index (LOI) tests, vertical burning testing (UL‐94), and cone calorimetry tests. Compared with neat EVA, the EVA/29(APP/TA)/1ZIF‐L composite exhibited an increased LOI from 20.1% to 24.6%, an improved UL‐94 rating from none to V‐0, and a 60.5% reduction in peak heat release rate (pHRR). Analysis of the decomposition products and char residue suggests a synergistic flame‐retardant effect in condensed phase and gas phase. Moreover, owing to the UV absorption of TA and ZIF‐L and the free‐radical scavenging ability of TA, the EVA composites exhibited significantly enhanced UV shielding, reaching an “excellent” level.