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采用SEM、XRD、TGA等分析方法对高抗冲聚苯乙烯/有机蒙脱土(HIPS/OMMT)纳米复合材料在燃烧过程中形成的炭渣残余物结构特征进行了研究,包括炭层断面形态,片层结构及炭渣热稳定性等.结果表明复合材料在热释放速率峰值之后,形成了具有阻燃作用的炭层结构,其特征是在炭层表面形成了一层比较薄但密实的皮层,皮层之下是较厚的一层蜂窝层,这种“皮-窝”结构赋予炭层良好的阻隔热的作用,减缓了热分解过程.XRD分析还表明原有插层结构经过燃烧已破坏,在皮-窝炭层中都已消失,结合SEM观察结果,蒙脱土片层多以剥离的单片层无规分布,皮层和窝层中聚合物已基本烧蚀,只剩下片状的蒙脱土聚集在一起形成了一种纳米尺寸的网状结构并包含了一定量的分解温度很高的碳质物质,不仅形成了稳定的保护层,而且碳质物质的生成也降低了材料分解挥发速率.窝层含有大量尺寸较大的空穴结构,隔气效果不如皮层,但显著地增大了炭层的体积,整体上能起到较大的隔热作用.二者共同构筑的皮-窝炭层结构在复合材料的燃烧过程中起到了阻燃的作用.
The structural characteristics of carbon residue formed during the combustion of high impact polystyrene / organic montmorillonite (HIPS / OMMT) nanocomposites were investigated by SEM, XRD and TGA. The results showed that the morphology of carbon layer , Lamellar structure and thermal stability of carbon residue.The results show that the composite material has a flame retardant carbon layer structure after the peak of heat release rate and is characterized by a thin but dense Under the cortex, the cortical layer is a thick layer of honeycomb layer, this “skin - nest ” structure gives the carbon layer a good barrier to heat, slowing down the thermal decomposition process.XRD analysis also shows that the original intercalated structure through Combustion has been destroyed, and disappeared in the skin-char layer. According to SEM observations, most of the montmorillonite layers are randomly distributed in the peeled monolayer. The polymers in the skin layer and in the layer have been ablated, leaving only The lower flakes of montmorillonite come together to form a nano-sized network and contain a certain amount of carbonaceous material with high decomposition temperature, which not only forms a stable protective layer, but also produces carbonaceous material Reduce the rate of material decomposition volatilization. Layer contains a lot Inch larger hole structure, the gas barrier effect is not as good as the cortex, but significantly increased the volume of the carbon layer, as a whole can play a greater role in thermal insulation. The combustion of the material played a role in flame retardant.