To achive excellent fire resistance, new microcapsule flame retardants (DMCAD and DMPPD) were prepared using 9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide combined with melamine cyanurate or melamine polyphosphate as the shell material and diatomite as the core material. The successful assembly of DMCAD and DMPPD was detailed characterized by Fourier transform infrared (FT‐IR) spectra, X‐ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). Meanwhile, the flame retardancy and thermal stability of the unsaturated polyester resin (UPR)/DMCAD and UPR/DMPPD composites were also studied. The addition of DMCAD and DMPPD effectively improves the flame retardance properties of UPR, and the effect of DMPPD was better. The limiting oxygen index (LOI) of UPR/DMPPD‐3 increased by 11.6% when compared with that of UPR, and the sample achieved V‐0 rating. Moreover, the peak heat release rate (pHRR) and the total heat release (THR) rate of UPR/DMPPD‐3 were reduced by 67% and 26%, respectively. Under nitrogen condition and air condition, UPR/DMPPD showed better thermal stability and char‐forming ability from the thermogravimetric (TG) results. Residual char of the UPR composites was systematically analyzed with SEM and XPS. Finally, the flame retardant mechanism of DMPPD was proposed.

中文翻译：

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硅藻土基微囊阻燃剂的制备及其不饱和聚酯树脂的防火安全性

为了获得优异的耐火性，使用9,10-二氢-9-氧杂-10-磷杂菲-10氧化物与三聚氰胺氰尿酸酯或三聚氰胺多磷酸酯为壳材料，并以硅藻土为原料制备了新型微胶囊阻燃剂（DMCAD和DMPPD）。核心材料。DMCAD和DMPPD的成功组装通过傅立叶变换红外（FT-IR）光谱，X射线光电子能谱（XPS）和扫描电子显微镜（SEM）进行了详细描述。同时，还研究了不饱和聚酯树脂（UPR）/ DMCAD和UPR / DMPPD复合材料的阻燃性和热稳定性。DMCAD和DMPPD的加入有效地改善了UPR的阻燃性能，而DMPPD的效果更好。与UPR相比，UPR / DMPPD-3的极限氧指数（LOI）增加了11.6％，样品达到V-0等级。此外，UPR / DMPPD-3的峰值放热率（pHRR）和总放热率（THR）分别降低了67％和26％。在氮气和空气条件下，根据热重（TG）结果，UPR / DMPPD表现出更好的热稳定性和成炭能力。用SEM和XPS系统分析了UPR复合材料的残留炭。最后提出了DMPPD的阻燃机理。用SEM和XPS系统分析了UPR复合材料的残留炭。最后提出了DMPPD的阻燃机理。用SEM和XPS系统分析了UPR复合材料的残留炭。最后提出了DMPPD的阻燃机理。