PEG ‐Regulated and Silane‐Bridged Magnesium Carbonate With Controllable Particle Size for High‐Performance Flame‐Retardant EVA Composites

In this study, polyethylene glycol (PEG) of different molecular weights was employed to regulate the growth of anhydrous magnesium carbonate (AMC). The resulting PEG‐2000‐modified AMC exhibited optimal particle size and enhanced dispersion in ethylene‐vinyl acetate (EVA). Then, AMC was subjected to surface modification with γ‐aminopropyltriethoxysilane (KH550) and chemical bridging with melamine cyanurate (MCA) via γ‐glycidoxypropyltrimethoxysilane (GPTMS), which was termed KMA. This unique structure significantly enhanced the dispersion of flame retardant components and their interfacial compatibility with the EVA matrix, making it possible to simultaneously improve flame retardancy and mechanical properties at high filler loadings. The EVA composite containing 50 wt% of KMA demonstrates superior flame‐retardant performance evidenced by the increase in limiting oxygen index (LOI) from 18.6% to 27.4% and a UL‐94 V‐1 rating. The peak heat release rate (pHRR) and peak smoke production rate (pSPR) are reduced by 69.6% and 52.1%, respectively. Compared to EVA/AMC composites, the tensile strength and elongation at break of EVA/KMA composites are increased by 10.4% and 5.8%, respectively. This work presents a novel strategy for AMC modification and the development of high‐performance flame‐retardant EVA composites.