将聚苯乙烯（PS）树脂与有机蒙脱土（Organic Montmorillonite，0MMT）进行熔融复合制备0MMT／PS复合材料，通过XRD和高分辨透射电镜（HRTEM）对OMMT／PS复合材料的微观结构进行了观察和分析。分别采用热重分析、高温热分解、水平燃烧、氧指数和锥形量热法研究了复合材料的热降解行为和燃烧性能。结果表明：用熔融复合法制备的OMMT／PS复合材料为插层型复合材料；与纯PS相比，加入少量有机黏土就可使OMMT／PS复合材料的阻燃性能得到明显改善；OMMT与PS质量比为2：100时OMMT／PS复合材料的热稳定性显著提高，质量损失10％和50％的温度可分别提高7．8℃和15．2℃，500℃的热分解残留率增加2．6％，氧指数增加1．4％，热释放速率峰值降低21．0％；OMMT片层对聚合物分子链的屏蔽作用以及燃烧时在复合材料表面生成的连续和致密的炭层残余物使聚合物免受进一步分解，降低了其分解速率；OMM／PS复合材料熔体黏度的增加降低了聚合物热分解产生的可燃小分子化合物向燃烧区域迁移的速率，减少了燃料供应。这两种因素的共同作用，增强了复合材料的阻燃性能。
Organoclay modified polystyrene composites were prepared by melt-compounding polystyrene （PS） resin and organic montmorillonite （OMMT）. The structures of the OMMT/PS composites were studied by XRD and high resolution TEM （HRTEM）. The pyrolysis behavior and fire performance of the composites were investigated by means of TC-A, high temperature degradation, horizontal burning, oxygen index and cone calorimetry experiments. The results indicate that the OMMT/PS composite is an intercalated composite. Compared with pure PS, adding a small amount of organoclay can evidently improve the flame retardancy of the OMMT/PS composite. The OMMT/PS composite with OMMT/PS mass ratio of 2/100 exhibits much higher thermal stability, of which the degradation temperature with 10% and 50℃ mass losses can increase by 7. 8 ℃ and 15. 2℃, respectively. The residue percentage at 500 ℃ and oxygen index rise by 2. 6% and 1.4%, respectively, while the peak heat release rate decreases by 21.0%. The shielding of OMMT layers to the intercalated polymer chains and the formation of a continuous and compact char residue layer, which covers on the burnt polymer composite surface, can prevent the polymer from further degradation and decrease its degradation rate. The increase of melt viscosity of the OMMT/PS composite decreases the transfer rate of the combustible small- molecular compounds to the flame zone and thus suppresses the supply of fuel to the fire. The flame retardancy of the composites is enhanced due to both factors.
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