溴系协效阻燃体系对PP阻燃和生烟性能的影响

摘要

利用极限氧指数、锥形量热仪和热重分析等方法对比研究了溴–锑和溴–铋协效阻燃体系对聚丙烯(PP)阻燃性能和生烟性能的影响。结果表明，八溴醚–氧化铋和八溴醚–三氧化二锑阻燃体系能明显提高PP的阻燃性能；当溴–锑和溴–铋阻燃剂的质量比为3∶1时，协同阻燃效果最佳，其中八溴醚–三氧化二锑和八溴醚–氧化铋的协同效率值分别为3.96和4.32。与纯PP相比，八溴醚的加入明显增大了PP的生烟速率(SPR)和总生烟量(TSR)，但溴–铋阻燃PP的SPR峰值和TSR相比于溴–锑阻燃PP却分别下降了14.94%和14.32%。热重分析表明，溴–铋阻燃体系相比于溴–锑阻燃体系能较早地释放出HBr，并更大程度地降低PP的热裂解速率，从而更有效地提高溴系阻燃PP的协同阻燃效率并降低生烟量。%The influences of bromine-antimony and bromine-bismuth flame retardant systems on the flame retardancy and smoke properties of polypropylene (PP) were studied by limited oxygen index,cone calorimeter and thermo-gravimetric analyzer. The results show that the flame retardant systems of tetrabromobisphenol A bis(2,3-dibromopropyl ether)(TBAB)-antimony trioxide (Sb2O3) and TBAB-bismuth oxide (Bi2O3) obviously improve the flame retardancy of PP. When both the mass ratio of TBAB-Sb2O3 and TBAB-Bi2O3 are 3∶1,the synergistic effects are the best,while the values of synergistic efficiency for TBAB-Sb2O3 and TBAB-Bi2O3 are 3.96 and 4.32 respectively. In addition,the peak SPR and TSR of bromine-bismuth system decrease by 14.94%and 14.32% respectively in comparison with bromine-antimony system treated PP,while both bromine-antimony and bromine-bismuth systems increase the SPR and TSR compared to pure PP. Thermal gravimetric analysis indicates that the higher synergistic effectiveness of bismuth oxide compared to antimony trioxide in the PP/TBAB mixture is contribute to bismuth oxide can catalyze the decomposition of TBAB at lower temperature and reduce the rate of volatilization of polypropylene.