焦磷酸哌嗪类阻燃剂阻燃PLA性能

Porperties of Piperazine Pyrophosphate Flame Retardants using in PLA

为研究自制的焦磷酸哌嗪类阻燃剂(FR-1420)对聚乳酸(PLA)的阻燃效果及阻燃机理,添加不同含量的FR-1420阻燃PLA,采用垂直燃烧、极限氧指数(LOI)、热重(TG)分析、锥形量热(CCT)、扫描电子显微镜(SEM)等测试手段对复合材料的性能进行了系统分析。结果表明,FR-1420质量分数为15%时,可使PLA的LOI提高至31%,垂直燃烧测试后样条表面形成致密的膨胀炭层,阻燃等级达到V-0级;TG结果表明,无卤阻燃PLA与纯PLA的热分解过程相似,但残炭率大幅度提高;CCT结果表明,FR-1420可以有效地降低PLA的火灾危险性,当FR-1420质量分数达到15%时,热释放速率峰值和总热释放速率分别降低至123 kW/m^(2)和22 MJ/m^(2),降低幅度分别为54%和50%,同时减缓了质量损失;残炭的SEM分析发现,FR-1420通过催化PLA形成封闭蜂窝状连续膨胀炭层,抑制可燃气体的挥发、隔绝氧气与热量的传递,从而达到优异的阻燃效果。

In order to study self made the flame retardance and mechanism of piperazine pyrophosphate flame retardant on polylactic acid(PLA),different contents of homemade flame retardant FR-1420 were added to flame retardant PLA.The properties of the composites were systematically analyzed by vertical burning test,limiting oxygen index(LOI),thermogravimetric(TG)analysis,cone calorimetric test(CCT)and scanning electron microscopy(SEM).The results show that when FR-1420 is added 15%,the LOI reaches 31%and vertical burning reaches V-0 grade.TGA shows that the thermal decomposition process of halogen-free flame retardant PLA is similar to pure PLA,but the carbon residue content is greatly increased at 700℃.CCT results show that FR-1420 can effectively reduce the fire risk of PLA.When the addition amount of FR-1420 reaches 15%,the peak heat release rate and total heat release rate reduces to 123 kW/m^(2) and 22 MJ/m^(2),respectively,reduces by 54%and 50%.At the same time,the mass loss is slowed down.Moreover,SEM shows that FR-1420 catalyzes PLA to form a closed honeycomb continuous expansion carbon layer,which inhibites the volatilization of combustible gas and isolated the transfer of oxygen and heat,thus achieving excellent flame retardant effect.