硝酸舍他康唑的热分解机理及动力学

采用热重法(TG)、差示扫描量热法(DSC)测定了硝酸舍他康唑(STCZ)在氮气氛和空气氛中的热分解过程,结果表明STCZ的热分解过程是一个三阶段过程。运用量子化学GAMESS软件计算了STCZ分子的键级,测定了STCZ及其在热分解过程中不同阶段残留物的红外光谱,推断了STCZ的热分解机理,起始步骤是硝酸的分解。根据不同升温速率下的热重曲线计算得到STCZ第一阶段热分解反应的动力学参数,在氮气中,表观活化能Ea=222.2 kJ.mol-1,指前因子A=4.467×1024min-1,在空气中,表观活化能Ea=177.2 kJ.mol-1,指前因子A=1.738×1019min-1。推算了不同使用温度下STCZ的预期寿命。

Thermal decomposition process of sertaconazole nitrate

The thermal decomposition process of sertaconazole nitrate(STCZ)was measured by means of thermogravimetry(TG) and differential scanning calorimetry(DSC).The results indicate that the thermal decomposition of STCZ is a three-stage process.The molecular bond orders were calculated by GAMESS method of quantum chemistry.The IR spectra of STCZ and its remainders in thermal decomposition at various temperatures are determined.The mechanism of the thermal decomposition of STCZ has been discussed.The decomposition of nitric acid occurs in the initial step.The parameters of thermal decomposition kinetics of STCZ are obtained with the values of the activation energy E_a=222.2 kJ·mol~(-1),pre-exponential factor A=4.467×10~(24) in N_2,and E_a=177.2 kJ·mol~(-1),A=1.738×10~(19) in air.The prospective lifetime of STCZ at different temperature is speculated by Dakin equation.