TY - EJOU AU - Huo, Xuan AU - Wu, Bingchen AU - Lou, Yuanmeng AU - Zhu, Junlin AU - Li, Cui AU - Ma, Lili AU - Pan, Ye-Tang AU - Hao, Chuncheng AU - Wen, Xin TI - Synergistic Effect of Silicone Macromolecular Charring Agent and Ammonium Polyphosphate on Improving Flame Retardancy and Mechanical Properties of Ethylene-Butyl Acrylate Copolymer Composites T2 - Journal of Polymer Materials PY - 2025 VL - 42 IS - 2 SN - 0976-3449 AB - Power cables are important pieces of equipment for energy transmission, but achieving a good balance between flame retardancy and mechanical properties of cable sheaths remains a challenge. In this work, a novel intumescent flame retardant (IFR) system containing silicone-containing macromolecular charring agent (Si-MCA) and ammonium polyphosphate (APP) was designed to synergistically improve the flame retardancy and mechanical properties of ethylene-butyl acrylate copolymer (EBA) composites. The optimal mass ratio of APP/Si-MCA was 3/1 in EBA composites (EBA/APP-Si-31), corresponding to the best flame retardancy with 31.2% of limited oxygen index (LOI), V-0 rating in UL-94 vertical burning test, and 76.4% reduction on the peak of heat release rate (PHRR) in cone calorimeter test. The enhancement mechanism was attributed to the synergistic effect of APP/Si-MCA during combustion, including the radical-trapping effect, the dilution effect of non-flammable gases, and the barrier effect of the intumescent char layer. Meanwhile, the tensile results indicated that EBA/APP-Si-31 also exhibited good mechanical properties with the addition of maleic anhydride-grafted polyethylene (PE-g-MA) as the compatibilizer. Thus, the APP/Si-MCA combination is an effective IFRs system for preparing high-performance EBA composites, and it will promote their applications as cable sheath materials. KW - Ethylene-butyl acrylate copolymer; intumescent flame retardants; polymer composites; synergistic effect; cable sheath DO - 10.32604/jpm.2025.065320