Herein, we have successfully synthesized phosphorus/nitrogen/silicon tri-elements compound phosphazene derivative hexa-[4-(N-(3-(triethoxysilyl)propyl)acetamide)phenoxy]cyclotriphosphazene (HNTPC) from hexachlorotriphosphazenitrile, methyl 4-hydroxybenzoate, and 3-triethoxysilylpropylamine, and it was used as an additive flame retardant in epoxy resin (EP). Then, the thermal stability and flame retardancy of the composite (HNTPC/EP) were tested. Thermogravimetric analysis showed that the presence of HNTPC made EP matrix decompose at a relatively low temperature, thus promoted the formation of a stable coke layer and protected the matrix from fire. Therefore, the amount of carbon residue was markedly increased at 800°C, indicating an outstanding condensed phase flame-retardant effect. Furthermore, various combustion test data manifested that the addition of HNTPC could significantly improve the flame-retardant performance of EP. In addition, the sample could pass the vertical burning tests (UL-94) V-1 grade when the addition amount was 10% and the limiting oxygen index value was 32.6%, the peak heat release rate and total heat release rate decreased by 40.0% and 21.5%, respectively. Besides, the results of scanning electron microscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy also showed that HNTPC can promote the formation of carbon layer and improved the flame-retardant property of EP. Finally, the condensed phase and gas phase synergistic flame-retardant mechanism of HNTPC was proposed.

中文翻译：

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多元磷腈衍生物的合成及环氧树脂阻燃性能研究

在此，我们以六氯三磷腈、4-羟基苯甲酸甲酯和4-羟基苯甲酸甲酯为原料，成功合成了磷/氮/硅三元复合磷腈衍生物六-[4-(N-(3-(三乙氧基甲硅烷基)丙基)乙酰胺)苯氧基]环三磷腈(HNTPC)。 3-三乙氧基甲硅烷基丙胺，在环氧树脂（EP）中用作添加剂阻燃剂。然后，测试了复合材料（HNTPC/EP）的热稳定性和阻燃性。热重分析表明，HNTPC的存在使EP基体在相对较低的温度下分解，从而促进了稳定的焦炭层的形成并保护了基体免受火灾。因此，800℃时残炭量显着增加，凝聚相阻燃效果显着。此外，各种燃烧试验数据表明，HNTPC的加入可以显着提高EP的阻燃性能。此外，当添加量为10%、极限氧指数值为32.6%时，样品可通过垂直燃烧试验（UL-94）V-1级，峰值放热率和总放热率降低40.0 % 和 21.5%，分别。此外，扫描电镜、拉曼光谱和X射线光电子能谱的结果也表明HNTPC可以促进碳层的形成，提高EP的阻燃性能。最后，提出了HNTPC的凝聚相和气相协同阻燃机理。当添加量为10%，极限氧指数值为32.6%时，样品通过垂直燃烧试验（UL-94）V-1级，峰值放热率和总放热率分别下降40.0%和21.5 ％， 分别。此外，扫描电镜、拉曼光谱和X射线光电子能谱的结果也表明HNTPC可以促进碳层的形成，提高EP的阻燃性能。最后，提出了HNTPC的凝聚相和气相协同阻燃机理。当添加量为10%，极限氧指数值为32.6%时，样品通过垂直燃烧试验（UL-94）V-1级，峰值放热率和总放热率分别下降40.0%和21.5 ％， 分别。此外，扫描电镜、拉曼光谱和X射线光电子能谱的结果也表明HNTPC可以促进碳层的形成，提高EP的阻燃性能。最后，提出了HNTPC的凝聚相和气相协同阻燃机理。X射线光电子能谱也表明HNTPC可以促进碳层的形成，提高EP的阻燃性能。最后，提出了HNTPC的凝聚相和气相协同阻燃机理。X射线光电子能谱也表明HNTPC可以促进碳层的形成，提高EP的阻燃性能。最后，提出了HNTPC的凝聚相和气相协同阻燃机理。