采用热重分析(TG)和热裂解气质联用(Py-GC/MS)方法研究了聚酰胺66纤维的热稳定性和热裂解机制。结果表明:聚酰胺66纤维在氮气气氛中的热分解过程为一步反应,热分解活化能为186.4 kJ/mol,470℃以上可完全分解,热稳定性良好。聚酰胺66纤维的热裂解产物主要是环戊酮,峰面积百分比达24.27%。 The thermal stability and pyrolysis mechanism of polyamide 66 fiber were studied by thermogravimetric analysis (TG) and pyrolysis gas chromatography-mass spectrometry (Py-GC / MS). The results showed that the thermal decomposition process of polyamide 66 fiber was a one-step reaction in a nitrogen atmosphere. The thermal decomposition activation energy was 186.4 kJ / mol. The thermal decomposition of polyamide 66 fiber was completely decomposed at 470 ℃ and the thermal stability was good. The pyrolysis product of polyamide 66 fiber is mainly cyclopentanone, with a peak area percentage of 24.27%.