Piperazine cyanurate (PCA) is designed and synthesized via hydrogen‐bonding self‐assembly reactions between piperazine and cyanuric acid. Chemical structure and morphology of PCA are investigated by Fourier transform infrared spectroscopy and scanning electron microscopy, respectively. The prepared PCA is combined with ammonium polyphosphate (APP) to prepare flame‐retardant polypropylene (PP) composites. Thermostability, flammability, and combustion characteristics of PP composites are analyzed. The maximum thermal decomposition rate of flame‐retarded PP composites has an apparent reduction compared with that of pure PP, and obvious char is left for this intumescent flame retardant (IFR) system of APP and PCA. A high limiting oxygen index value and UL‐94 V‐0 rating are achieved with addition of APP and PCA. In cone calorimetry test, heat and smoke releases of PP are significantly decreased by this IFR system. Gaseous decomposition products during the thermal decomposition of flame‐retardant composites are studied. Chemical structure and morphology of char residues are analyzed. The results illustrate that APP and PCA have a superb synergistic action in the aspect of improvement in fire safety of PP. A possible flame‐retardant mechanism is concluded to reveal the synergism between APP and PCA.

中文翻译：

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氢键自组装反应制备氰尿酸哌嗪及其在膨胀型阻燃聚丙烯复合材料中的应用

哌嗪氰尿酸酯（PCA）是通过哌嗪与氰尿酸之间的氢键自组装反应设计和合成的。分别通过傅里叶变换红外光谱和扫描电子显微镜研究了五氯苯甲醚的化学结构和形态。将制备的PCA与多磷酸铵（APP）结合在一起，以制备阻燃聚丙烯（PP）复合材料。分析了PP复合材料的热稳定性，可燃性和燃烧特性。与纯PP相比，阻燃PP复合材料的最大热分解速率有明显降低，并且APP和PCA的这种膨胀型阻燃（IFR）系统还留有明显的炭。通过添加APP和PCA，可以达到较高的极限氧指数值和UL-94 V-0等级。在锥形量热法测试中 通过该IFR系统，可显着降低PP的散热和烟气释放。研究了阻燃复合材料热分解过程中的气态分解产物。分析了焦炭残渣的化学结构和形态。结果表明，APP和PCA在改善PP的防火安全方面具有极好的协同作用。得出了一种可能的阻燃机制，以揭示APP和PCA之间的协同作用。