新型硅-氮协同阻燃剂的合成及应用

Synthesis and Application of a Novel Si-N Synergistic Flame Retardant

以三聚氰胺钠盐和二苯二氯硅烷为原料,合成了一种新型有机硅-氮协同阻燃剂二苯基硅酰二密胺。其最佳反应条件为,氮气保护下,以1,2-二氯乙烷为溶剂,三聚氰胺钠盐与二苯二氯硅烷的摩尔比为2.15∶1,在80℃下反应7 h,降温至30℃后减压过滤,蒸馏水洗涤,干燥后得到产物,产率为92.5%。通过红外光谱(FTIR)、核磁共振氢谱(1H-NMR)、差热分析(TG-DTA)等分析了产物的结构和热稳定性,将产物应用于886不饱和树脂,进行了极限氧指数(LOI)、垂直燃烧测试及力学测试。结果表明,产物结构与目标化合物一致,硅氮以共价键结合,酰胺结构稳定;产物初始分解温度为285℃,最终残炭量为52%,具有较好的热稳定性能;将其应用于886不饱和树脂材料,当产物添加量为25%时,阻燃样条的LOI达到30%,阻燃等级为UL 94 V-0级,具有较好的成炭性和阻燃效果,同时具备一定的增塑性。通过残炭SEM分析了阻燃机理,也进一步证明了产物优良的硅-氮协同阻燃效能。

A novel organic Si-N synergistic flame retardant diphenylsilylacyl bismelamine was synthesized from sodium melamine and diphenyldichlorosilane.The optimum synthesis route was investigated as follows:n(sodium melamine):n(diphenyldichlorosilane)=2.15:1,1,2-dichloroethane as solvent and keeping the reaction at 80℃ for 7 h under nitrogen atmosphere,filtered after cooling to 30℃,the yield was 92.5%after washing and drying.The structure and thermal stability of the product was tested by FTIR,1H-NMR and TG-DTA.The limit oxygen index(LOI),vertical flammability and mechanical property was tested when it was applied to 886 unsaturated resin.Results showed that the amide structure of the product was stable,and silicon nitrogen was bound by covalent bond.The initial decomposition temperature of the product was 285℃,and the final carbon residue was 52%.The product had an excellent thermal stability,presented certain plasticization and a good effect on antiflaming when it was applied to 886 unsaturated resin,when the product content was 25%,the LOI of the flame retardant sample reached 30%,and the flame retardant grade was UL 94 V-0.The mechanism of flame retardancy was analyzed by SEM of carbon residue,which further proved the excellent Si-N flame retardant effect of the product.