In order to improve the flame retardancy of polyurethane waterborne coatings, a reactive phosphorus and nitrogen containing monomer, designated as HO₂-N₂P₄, was synthesized and characterized, and then incorporated at various levels into polyurethane via copolymerization. The monomers and poly(urethane) copolymers were characterized and analyzed using Fourier transform infrared spectroscopy, nuclear magnetic resonance spectroscopy, scanning electron microscopy, thermogravimetric analysis, and cone calorimetry. Even at low levels of HO₂-N₂P₄ incorporation, all the copolymers exhibit reduced thermal degradation rate and reduced flammability compared to the same properties for polyurethane containing no comonomer. Furthermore, it was observed that the flame retardant effect for the copolymers was positively correlated with the HO₂-N₂P₄ content.

中文翻译：

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一种新型含磷-氮本征阻燃水性聚氨酯共聚物

为了提高聚氨酯水性涂料的阻燃性，合成并表征了活性磷氮单体HO ₂ -N ₂ P ₄，然后通过共聚反应将其以不同水平掺入聚氨酯中。使用傅里叶变换红外光谱、核磁共振光谱、扫描电子显微镜、热重分析和锥形量热法对单体和聚（氨基甲酸酯）共聚物进行了表征和分析。即使在低水平的 HO ₂ -N ₂ P ₄与不含共聚单体的聚氨酯相比，所有共聚物的热降解速率和可燃性均降低。此外，观察到共聚物的阻燃效果与HO ₂ -N ₂ P ₄含量呈正相关。