热氧老化对红磷阻燃长玻纤增强聚丙烯复合材料性能及热降解行为的影响

Effects of Thermal-Oxidative Aging on Properties and Thermal Degradation Behaviors of Red Phosphorus Flame Retardant Long Glass Fiber Reinforced Polypropylene Composites

采用热烘箱老化法,在120℃条件下,研究不同热氧老化时间对熔融共混法制备的红磷阻燃长玻纤增强聚丙烯(LGFPP)复合材料性能及热降解行为的影响。结果表明,与未老化时相比,热氧老化30 d时,复合材料的极限氧指数达到最大值,为27.4%,质量保持率达到最大值,为28.48%。能谱分析结果表明,红磷阻燃剂会出现一定程度的部分迁移现象,当热氧老化50 d时,复合材料的拉伸强度、弯曲强度和缺口冲击强度保持率分别为61.58%,52.96%和72.35%。表明一定程度的热氧老化,可使复合材料的阻燃性能有所提升,但分子量降低,力学性能下降严重。热氧老化是红磷阻燃LGFPP复合材料性能及热降解行为的重要影响因素。

The thermal-oxidative aging method is adopted, the red phosphorus flame retardant long glass fiber reinforced polypropylene（LGFPP） composites were prepared by melt blending red phosphorus LGFPP and pure PP, the effects of thermaloxidative aging on the properties and thermal degradation behaviors of the red phosphorus flame retardant LGFPP composites were studied in the different time under the condition of 120℃. Results show that compared with no aging test specimen, when thermaloxidative aging time is 30 days, the limit oxygen index of the composite reaches a maximum value of 27.4%, the residual carbon amount achieves a maximum value of 28.48%. The energy spectrum analysis results demonstrate that the flame retardant appears a certain degree of partial migration phenomenon. When thermal-oxidative aging time is 50 days, the tensile strength, bending strength and notched impact strength of the composite are 61.58%, 52.96% and 72.35% respectively. With some degree of thermal oxidative aging, it shows that the flame retardant properties of the composite have been improved, but the molecular weight and mechanical properties decreased seriously. The thermal-oxidative aging is a important influencing factor of performance and thermal degradation behaviors of the red phosphorus flame retardant LGFPP composites.