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Phosphorus and nitrogen-containing curing agents were obtained from the reaction of phosphorus oxychloride or phenylphosphonic dichioride with different amounts of aziridine in this study. The aziridinyl groups of thses curing agents were reactive toward carboxylic groups of aqueous-based polyurethanes at a lower pH value conditions. Phosphorus and nitrogen both existed in PU, they behaved a synergistic effect on polymer flame inhibition. PU was cured by these dual-function curing agents, respectively. Flame retardancy and the performance properties of PU were improved after this type curing reaction. The physical and mechanical properties, such as, gel content, water uptake, ethanol swollen, tensile strength and etc. were investigated. Whereas its thermal and flame retardancy of PU were evaluated by dynamic mechanical analysis, thermogravimetric analysis, limited oxygen index and cone calorimeter.
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