Thermal stability of poly （vinyl chloride） （PVC）/lignin blends was studied with thermogravimetric analysis. It was shown that the thermal stability depended on the integration of two behaviors, sterically hindered phenol structure of lignin could improve thermal stability of the blends; dehydration of lignin could decrease thermal stability of the blends. In the early stage of the decomposition, the latter was dominant, and the early thermal stability of the blends was worse than that of PVC. In the medium-term of the decomposition, thermal stability of the blends was better than that of PVC due to the end of dehydration, and the former turned to predomination in this stage.%采用热重分析法研究了聚氯乙烯（PVC）／木质素共混物的热稳定性。结果表明，共混物的热稳定性取决于2个相反效应的叠加效果：一是木质素分子中的受阻酚类结构单元具有捕捉热降解中形成的自由基的功能，因此可以改善共混物的热稳定性；二是木质素在150-250℃的温度区间内会发生轻微的脱水现象，水分对PVC的自催化脱氯化氢过程具有促进作用，因此会降低PVC的热稳定性。在热分解初期，后者起主要作用，共混物的早期热稳定性有所降低；但当木质素在更高温度下完成脱水后，前者变成主要作用，共混物的中期热稳定性有明显提升。
展开▼
