溴-锑-磷协效阻燃体系对聚丙烯土工格栅阻燃和生烟性能的影响

利用极限氧指数、垂直燃烧试验、酒精喷灯燃烧试验、锥形量热仪、热重分析和力学性能测试等手段研究了溴-锑-磷阻燃体系对聚丙烯(PP)土工格栅的力学性能、燃烧性能、生烟性能和热解特性的影响。结果表明,低添加量(质量分数≤5%)的溴-锑-磷阻燃体系对PP土工格栅的拉伸强度和断裂伸长率影响较小,但明显提高了材料的阻燃性能,其中质量分数5%的四溴双酚A-双(2,3-二溴丙基醚)(八溴醚)-三氧化二锑阻燃PP的峰值热释放速率(HRR)和总释放热(THR)相比于纯PP分别下降了39.98%和26.03%。八溴醚-三氧化二锑阻燃体系与红磷复配时还表现出较好的协效作用,当溴-锑与磷的质量比为3∶2时,协效阻燃效果最优,仅添加5%的协效阻燃体系便可使PP的LOI和UL 94等级分别达到27.9%和V-0级,并通过酒精喷灯燃烧试验。与纯PP相比,溴-锑阻燃体系虽降低了PP的HRR和THR,但增大了燃烧过程中的生烟速率(SPR)和总产烟量(TSR),而红磷的加入能有效降低溴-锑阻燃PP的生烟量。热重分析表明,溴-锑-磷协效阻燃体系表现出较好的气相阻燃作用,能有效降低PP的热裂解速率,增强了PP的阻燃性能。

Impact of TBAB-Sb2O3 and the red phosphorus on the flame and smoke emission performance of polypropylene in the geo-grid

The present paper is aimed to make an exploration of the synergistic effect of the red phosphorus (RP) with the bromine-antimony flame retardant system in polypropylene (PP) intended for the geo-grid.In the paper,we have also made an investigation of the flammability and the smoke suppression performance of the said flame retarding PP by means of the limited oxygen index (LOI),the UL 94,the alcohol-spray lamp test,the cone calorimeter and the thermo-gravimetric analyzer (TGA).In addition,we have also examined the tensile strength and elongation at break of flame retarded PP through the mechanical performance test.The results of our investigation and tests show that both the tensile strength and elongation at the break of the flame retarding PP tend to reveal a slight decrease on the condition when the flame retardant system works at a rate of 5wt％.However,the flame retardancy of the PP composites can be expected to be significantly promoted on the condition when the system can be added by a 5wt％ of tetrabromobisphenol A bis(2,3-dibromopropyl ether) (TBAB)-antimonytrioxide (Sb2O3).Actually,the peak heat release rate and the total heat release of the flame retarded PP at a 5wt％ of the TBAB-Sb2O3 flame retardant can help to decrease by about 39.98％ and 26.03％ as compared with the pure PP.Besides,an obvious synergistic flame retardant effect can also be found between the TBAB-Sb2O3 flame retardant and the RP.However,if the ratio of the mass of TBAB-Sb2O3 and RP is chosen to be 3∶2 with the total mass content rate being 5wt％,it would be possible for PP to reach its optimal LOI value of 27.9％ whereas the UL 94 can be made to reach V-0 grade,respectively,for they can facilitate the alcohol lamp test.It can also be noticed that adding of the bromine-antimony flame retardant can prolong the heat release rate and the total heat release effectively,though it is likely to promote the smoke production and the total smoke release of the composites,as compared with the pure PP.What is more,when RP is added to the bromine-antimony flame retardant system as a synergistic agent,it would be possible to reduce the smoke production of the said PP in comparison with the bromine-antimony system treated PP.Thus,the TGA results demonstrate that the TBAB-Sb2O3-RP flame retardant system can significantly reduce the volatilization rate of polypropylene in the process of pyrolysis,which can promote the flame retardancy of the aforementioned PP to be used for the geo-grid.