阻燃共聚酯／蒙脱土纳米复合材料的裂解和阻燃机理研究

Mechanism of pyrolysis and fire retardancy for copolyester/montmorillonite nanocomposites

通过裂解色谱质谱分析，热重分析，XRD和SEM等方法，对实验室合成的一种阻燃共聚酯，蒙脱土纳米复合材料的裂解和阻燃机理进行研究．分析结果表明蒙脱土和阻燃共聚酯DDP的加入都能减少PET裂解过程中可燃小分子化合物的产生，抑制PET的深度裂解反应，同时降低PET起始分解温度．此外，DDP能够有效改善材料燃烧过程中的失重率，抑制PET裂解过程中的自由基反应，而蒙脱土在燃烧过程中随着温度升高，会在炭层表面产生堆积，改变炭层形貌，提高其热稳定性．研究还表明，两者在改善炭层质量，增强其隔热隔氧性能方面存在着协同作用。

The mechanism of pyrolysis and fire retardancy for one copolyester/montmorillonite nanocomposite was investigated using Py-GC-MS, TG, XRD and SEM methods. The results show the contents of flammable small-molecular volatile compounds are distinctly reduced, and the initial decomposition temperature of PET decreases remarkablly after the addition of both montmorillonite and the flame retardant DDP. Moreover, the amount of char residue increases, and radical mechanism is inhibited in the pyrolysis of PET due to the presence of DDP. Meanwhile, montmorillonite accumulates on the surface of char with the increment of temperature, which reinforces of the thermal stability of char. The study still indicates synergic effects exist between MMT and DDP in improving the quality of char and enhancing its baffling property for oxygen and heat.