PA6/蒙脱土复合材料的炭层结构对阻燃性能的影响

Effect of Fire Residue Structure on Flame Retardant Properties of PA6/Montmorillonite Composites

采用熔融插层法制备了含有无机蒙脱土(MMT)和有机蒙脱土(OMMT)的PA6(尼龙6)/MMT和PA6/OMMT复合材料,并通过锥形量热仪评价了复合材料的阻燃性能;采用数码相机、扫描电镜(SEM)观察了燃烧残余物的宏观、亚微观和微观结构。结果表明,OMMT能明显降低复合材料的热释放速率和质量损失速率,PA6/OMMT纳米复合材料燃烧中形成的炭渣具有特殊的皮层-蜂窝层复合的亚微观结构,并在微观上具有网络结构,二者共同作用构成了有效的阻隔层,降低了材料的可燃性。

The montmorillonite （MMT） and organically modified montmorillonite （OMMT） were respectively employed to prepare PA6/MMT and PA6/OMMT composites through the melting intercalation method. The flame retardancy of composites was evaluated by the cone calorimeter. The macro-structure, submicro-structure and micro-structure of fire residues were examined by digital camera and scanning electron microscope （SEM）. The results show that the heat release rate and mass loss rate of the composites are reduced significantly by the addition of OMMT. It is also found that the fire residue of PA6/OMMT is composed of a skin-cellular layer in submicro scale,and a network structure in microscale. The well combination of the skin-cellular layer and the network structure acts as an effective barrier to reduce flammability of the composites.