Abstract A high molecular weight DOPO-based flame retardant (DP-DE) containing phosphorus linked pendent groups was synthesized by a two-step esterification and polycondensation reaction, and characterized by Fourier transform infrared spectroscopy (FTIR), 13C nuclear magnetic resonance (13C NMR) and gel permeation chromatography (GPC). After added into polyethylene terephthalate (PET) via melt-blending method, the flame retardancy of DP-DE were monitored by thermo-gravimetric analysis (TGA), limiting oxygen index (LOI) and underwriter laboratories (UL-94) test. The results showed that DP-DE display good flame retardancy in PET. And the thermal stability, char residue yield and LOI values of the composites increased with the increase of DP-DE content. The flame retarded mechanism of DP-DE was investigated by pyrolysis-gas chromatogram-mass (PY-GC-MS), in situ FTIR, scanning electron microscope (SEM) and laser Raman spectroscopy (LRS). DP-DE was evidenced to release phosphorus acid and its derivatives, which catalyze carbonization and produce compact carbonaceous layers. Through protecting the polymeric materials substrate from further degradation and inhibiting the pyrolysis degree, both the amount and thermal stability of carbonaceous layers of DP-DE were improved, and hence enhancing the flame retarded performance of PET/DP-DE composites.

中文翻译：

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一种DOPO基高分子阻燃剂的合成、表征及其在聚对苯二甲酸乙二醇酯中的应用

摘要 通过两步酯化和缩聚反应合成了一种含磷连接侧基的高分子量 DOPO 基阻燃剂 (DP-DE)，并通过傅里叶变换红外光谱 (FTIR)、13C 核磁共振 (13C NMR) 表征。 ) 和凝胶渗透色谱 (GPC)。通过熔融共混法添加到聚对苯二甲酸乙二醇酯（PET）中后，DP-DE的阻燃性通过热重分析（TGA）、极限氧指数（LOI）和保险商实验室（UL-94）测试进行监测。结果表明DP-DE在PET中表现出良好的阻燃性。随着DP-DE含量的增加，复合材料的热稳定性、残炭率和LOI值增加。通过热解-气相色谱-质谱(PY-GC-MS)、原位FTIR、扫描电子显微镜(SEM)和激光拉曼光谱(LRS)研究了DP-DE的阻燃机理。DP-DE 被证明会释放磷酸及其衍生物，催化碳化并产生致密的碳质层。通过保护高分子材料基材不被进一步降解和抑制热解程度，DP-DE碳质层的数量和热稳定性均得到改善，从而增强了PET/DP-DE复合材料的阻燃性能。