聚磷酸铵(APP)阻燃剂对聚丙烯(PP)性能的影响

Property of Polypropylene with Addition of Ammonium Polyphosphate Flame Retardant

采用熔融共混挤出法制备了聚磷酸铵/聚丙烯(APP/PP)阻燃复合材料。通过FTIR、SEM、DTA及熔体流动速率(MFR)对复合材料进行了测试和表征,并对其力学性能和阻燃性能进行了对比分析。讨论了APP的添加量对阻燃复合材料熔体流动速率、热力学行为、结晶行为、力学性能和断口形貌的影响。结果表明,阻燃剂APP的添加明显地降低了PP的燃烧性,APP在复合材料燃烧过程中有催化成炭和防融滴的作用;随着添加量的增加,复合材料的热力学稳定性增加,MFR值先降低后增加;当APP含量(质量分数)大于13%时,APP对PP的结晶存在异相成核作用,这种作用不仅影响着复合材料的力学性能,使得其力学性能不会随APP添加量的增大而继续下降;同时还提高了APP与PP基体间的界面结合。

Ammonium polyphosphate（APP）/polypropylene（PP）composites were prepared by melt blending and extrusion from a twin screw extruder.APP was used as a flame retardant for PP.FTIR,SEM,DTA and melting flow rate（MFR）were used to test and characterize APP/PP flame-retardant composites.Combustion performance and mechanical properties were also discussed.The effects of APP loading on melt flow rate,thermal behavior,crystallization behavior,mechanical properties and section structure of PP composites was further investigated.The results show that the addition of APP significantly reduced the combustion performance of PP,because APP effectively promoted the char formation and avoided droplet occurence.With the addition of APP,the thermal stability of APP/PP composites was increased,while MFR was decreased at first and then increased.The interface binding force between the flame retardant and the substrate was improved owing to heterogeneous nucleation of APP when APP loading was greater than 13%,which also inhibited the declining of the mechanical properties of APP/PP composites.