以聚碳酸酯二醇、异氟尔酮二异氰酸酯为原料,添加不同用量的聚磷酸铵(APP),制备了一系列阻燃水性聚氨酯。UL-94测试表明,随着APP添加量的增大,水性聚氨酯的阻燃性逐渐增大。锥形量热仪测试表明,随着APP含量从0%增加25%,水性聚氨酯的点燃时间由29 s延长到45 s,最大热释放速率(HRR)由413.2 k W/m2降低到314.3 k W/m2。热重测试表明,水性聚氨酯膜的热稳定性随着APP含量的增加而逐渐升高,当APP为25%时,热稳定性最好。力学性能测试表明,随着APP含量的增加,涂膜的拉伸强度及断裂伸长率逐渐下降。综合考虑以上因素,阻燃水性聚氨酯中聚磷酸铵的适宜用量为20%。
A series of flame-retardant waterborne polyurethane were prepared with polycarbonate diol and isophorone diisocyanate as raw materials and by addition of different amounts of ammonium polyphosphate (APP). UL-94 test showed that the flame retardance of waterborne polyurethane is increased with increasing dosage of APP. Cone calorimeter test indicated that the increasing of APP content from 0% to 25%, the ignition time of waterborne polyurethane is extended from 29 s to 45 s, and the peak heat release speed (HRR) is decreased from 413.2 kW/m^2 to 314.3 kW/me. Thermogravimetric analysis revealed that the thermal stability of waterborne polyurethane is improved gradually with increasing APP content up to 25%. Mechanical performance test proved that the increasing of APP content decreases the tensile strength and elongation at break of the film gradually. Comprehensively taking the above factors into account, the suitable dosage of APP in flame-retardant waterborne polyurethane is 20%.