聚碳酸亚丙酯马来酸酐的热分解动力学(英文)

Thermal Decomposition Kinetics of Poly(propylene carbonate maleate)

通过热重分析研究了新型三元共聚物聚碳酸亚丙酯马来酸酐(PPCMA)在不同升温速率下的热分解动力学.设计并引入一种新的计算方法,非线性约化法(NLA),对共聚物热分解过程中的表观活化能进行了计算.研究发现,虽然用非线性约化法计算的表观活化能相对误差值稍大于用传统计算方法Flynn-Wall-Ozawa(FWO),Tang和Kissinger-Akahira-Sunose(KAS)计算的相对误差值,但其分析合理且计算过程更为简便.此外,固态反应模型拟合方法计算结果表明,共聚物的热分解过程对应多个反应机理.整个热分解过程,表观活化能值处于70-135kJ·mol-1之间,指前因子处于5.24×104-9.89×107min-1之间.同时,通过对表观活化能值的比较,初步解释了聚碳酸亚丙酯(PPC)与PPCMA热解温度差异的原因.

The thermal decomposition kinetics of the novel terpolymer, poly（propylene carbonate maleate） （PPCMA）, was investigated using thermogravimetric （TG） analysis at different heating rates. A new computational method called nonlinear approximation （NLA） is introduced in this work. The Flynn-Wall-Ozawa （FWO）, Tang, Kissinger-Akahira- Sunose （KAS）, and NLA methods were used to calculate the apparent activation energy （Ea）. The results show that the NLA method is ideal for Ea calculations because of its simpler and more appropriate analysis process. It does, however, give slightly higher average relative errors for Ea compared to the other typical model-free methods. Calculations using the solid-state reaction model-fitting method indicated that the thermal decomposition process was composed of multiple mechanisms. For the whole decomposition process, the values of Ea were between 70 and 135 kJ·mol-1, and the pre-exponential factor （A） varied from 5.24×104 to 9.89×107 min-1. The differences in Ea also explain the differences in decomposition temperature between poly（propylene carbonate） （PPC） and PPCMA.