In-situ coprecipitation formed Fe/Zn-layered double hydroxide/ammonium polyphosphate hybrid material for flame retardant epoxy resin via synergistic catalytic charring

Inspired by the in-situ coprecipitation technology, Fe/Zn-layered double hydroxides (Fe/Zn-LDH) doped ammonium polyphosphate (APP) was prepared for high fire-safety epoxy resins (EP). The investigation on the chemical composition and micromorphology of Fe/[email protected] confirmed the uniform deposition of Fe/Zn-LDH on the surface of APP. The results showed that EP containing 4 wt% Fe/[email protected] exhibited the highest LOI of 29.4% and passed the UL-94 V0 level. Additionally, compared to neat EP, the peak of heat release rate, peak of smoke production rate, and the fire growth rate decreased by 66.4%, 48.4%, and 80.7%. The greatly enhanced flame retardancy of EP was contributed to the highly synergistic charring catalysis via abundant interfacial contact sites. Moreover, the mechanical performance of Fe/[email protected]/EPs were slightly affected due to the improved interfacial interaction of Fe/[email protected] Generally, this work exploited a tactful strategy to construct LDH doped APP hybrid material, and presented the potential application in industry.