In view of the problem that epoxy resin cannot achieve effective flame retardancy, smoke and toxic gas suppression functions in fire, and poor interface compatibility with flame retardants, a coreshell structure with SiO 2 as the nucleus was designed, and a new multi-component flame retardant was prepared by introducing Ni and phytic acid using metalorganic frameworks (MOFs) as precursors. After mixing and curing with epoxy resin, the SiO 2 /CoNi-DH-PA/EP was obtained. With only 5% SiO 2 /CoNi-DH-PA added, the peak heat release, total smoke production, and total CO production of epoxy resin composites are reduced by 63.72%, 31.88%, and 63.74%, respectively, and the residue yield increased from 15.05% to 24.40%. It has been verified that SiO 2 , Co-Ni bimetallic ions and phytic acid have synergistic effects, which can induce and catalyze the formation of a complete and dense carbon layer. This significantly reduces the heat release, smoke, and toxic gas production, thereby reducing the fire hazard of epoxy resin. Additionally, the SiO 2 /CoNi-DH-PA/EP ensures good mechanical properties.
Zhuang et al. (2025) studied this question.