Mechanism and Kinetics of Thermal Decomposition for 2-(4-methoxycarbonylphenyl)-5-amino-6-hydroxybenzoxazole

The thermal decomposition of 2-(4-methoxycarbonylphenyl)-5amino-6-hydroxybenzoxazole(MAB)is mensurated by thermogravimetry(TG),the IR spectra of MAB and its intermediates in thermal decomposition at various temperatures are determined,the molecular bond orders are calculated by GAMESS method of quantum chemistry,and also discussed is the mechanism of the thermal decomposition of MAB.All the results indicate that the thermal decomposition of MAB is a five-stage process.The O-C bond breakdown and the methoxy group disintegration occurr in the initial step of the decomposition and the parameters of thermal decomposition kinetics for MAB,such as activation energy(Ea=157.1 kJ·mol-1)and pre-exponential factor(A=3.715×1013)are obtained by thermogravimetry.