纤维素油酸酯热性能及热降解动力学

摘要

Thermal degradation and kinetics of cellulose oleate(CO) with different degree of substitution(DS) in argon were studied by thermogravimetry(TG) and diferential scanning calorimetry(DSC). In order to calculate the kinetic parameters of the thermal decomposition, such as reactive order(n), activation energy(E,) and frequency fac-tor(A), Kissinger s method and Coats-Redfern s method were applied. The parameters calculated were suitable in the range from initial degradation temperature( Td) to the maximum rate of degradation temperature(Tp). It was found that the reactive order(n) of CO reduced from 2. 9 of SI to 1. 4 of S3, as well Td and Tp decreased with increasing of DS; the E., A and thermal stability of CO decreased with increasing of DS.%利用热重法(TG)和差示扫描量热法(DSC)研究了不同取代度的纤维素油酸酯(CO)在氢气中的热降解及热降解动力学.为确定CO的热降解动力学参数,首先采用Kissinger法计算反应级数n,再利用Coats-Redfem法计算活化能Ea和频率因子A,计算结果适用于起始降解温度(Td)到最大降解速率温度(Tp)附近的温度范围.计算结果表明,CO热降解反应级数n随取代度的增加由2.9(S1)下降为1.4(S3)；CO的Td和Tp均随取代度的增加而降低,说明CO的热稳定性随取代度的增加而降低；活化能Ea和频率因子A同样随取代度的增加而降低.