In order to improve its water resistance and compatibility with polymer matrix, ammonium polyphosphate (APP) is modified with melamine‐trimesic acid (MEL‐TA) aggregates by supramolecular self‐assembly technology. Chemical structure and morphology of APP@MEL‐TA are investigated by Fourier transform infrared spectroscopy and scanning electron microscopy (SEM), respectively. Intumescent flame retardant system of APP@MEL‐TA and charring‐foaming agent is introduced into polypropylene (PP) matrix. The flammability and combustion behavior of PP composites are investigated by limiting oxygen index (LOI), UL‐94 vertical burning, and cone calorimetry tests. In terms of LOI values and cone combustion results, APP@MEL‐TA performs better than pristine APP. Char residue of PP composites is investigated by SEM and Raman spectra. Flame retardant mechanisms are proposed based on thermal decomposition, combustion results, and analysis on char residue.

中文翻译：

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聚磷酸铵的超分子自组装改性及其在聚丙烯中的阻燃应用

为了提高其耐水性和与聚合物基体的相容性，通过超分子自组装技术将三聚氰胺-三甲磺酸（MEL-TA）聚集体改性了聚磷酸铵（APP）。APP @ MEL-TA的化学结构和形态分别通过傅里叶变换红外光谱和扫描电子显微镜（SEM）进行了研究。将APP @ MEL‐TA的膨胀型阻燃体系和炭化发泡剂引入聚丙烯（PP）基体中。通过极限氧指数（LOI），UL‐94垂直燃烧和锥形量热测试研究了PP复合材料的可燃性和燃烧行为。在LOI值和圆锥燃烧结果方面，APP @ MEL‐TA的性能优于原始APP。通过SEM和拉曼光谱研究了PP复合材料的炭残留。