关键词: 青蒿素, DSC, 非等温动力学, Gaussian模拟, 贮存期

Abstract: Thermal decomposing curves of artemisinin at different heating rates were obtained under dynamic conditions in nitrogen atmosphere using non-isothermal differential scanning calorimetry analysis (DSC). Three thermal analysis kinetic methods (Kissinger, Flynn-Wall-Ozawa and Phadnis) were used to speculate the probable mechanism of thermal decomposing reaction and the kinetic parameters while the purity and melting point of artemisinin were obtained by Van'Hoff equation. The shelflife of artemisinin at room temperature was calculated by the kinetic parameters of the thermal decomposition. With the increasing of the heating rate, thermal analysis tempreture of artemisinin rose. The most probable kinetic mechanism of the thermal decomposition was two-dimensional diffusion which corresponded to Jander Equation. In accordance with the datas of atomic charges and bond orders by Gaussian simulation, the mechanism was identical with that artemisinin was decomposed into three compounds at 190 ℃. The shelflife of artemisinin at room temperature was about 3 years based on the apparent activation energy (E_a) and pre-exponential factor (A) of the thermal decomposition.

Key words: artemisinin, DSC, non-isothermal kinetics, Gaussian simulation, shelflife