【摘要】 以聚磷酸为初始反应原料,尿素为氨化缩合剂,经预聚合和高温固化2个阶段反应制得聚磷酸铵。针对预聚合反应过程中体系随温度变化由液态转化为固态的复杂过程,探讨了升温速率、温度和时间与表观粘度的关系以及反应压力对预聚合过程的影响。在最佳预聚合反应条件下合成的聚磷酸铵聚合度可以达到65.36,氨氮含量和磷含量分别为14.36%和69.84%(均为质量分数)。更多还原

【Abstract】 Ammonium polyphosphates(APP)were prepared by the polyphosphoric acid with urea as ammoniation polycondensation agent.The whole process of APP polycondensation was composed of two steps:first prepolymerization and second solidification and ageing treatment.In the process of prepolymerization the reaction system was transformed from liquid to solid with temperature.By experiments,the effect of heating rate on the properties of APP,the relationship of reaction temperature,time and apparent viscosity,and influence of the reaction pressure on the degree of polymerization were discussed.Under the conditions,the polymerization degree of APP was 65.36,and the content of NH3-N and P2O5were 14.36%and 69.84%(mass),respectively.更多还原