阿司匹林的热解机理及热动力学研究  

Studies on Thermal Decomposition Mechanism and Kinetics of Aspirin

作　　者：徐芬[1] 孙立贤[1] 谭志诚[1] 梁建国[2] 周丹红[3] 邸友莹[1] 兰孝征[1] 张涛[1] 

机构地区：[1]中国科学院大连化学物理研究所材料热化学实验室,大连116023 [2]湖南省药品检验所,长沙410000 [3]辽宁师范大学化学系,大连116029

出　　处：《物理化学学报》2004年第1期50-54,共5页Acta Physico-Chimica Sinica

基　　金：国家自然科学基金(20073047)资助项目~~

摘　　要：在用热重法研究了阿司匹林的热稳定性实验的基础上,通过量子化学方法(abinitioDFT)计算了阿司匹林分子的键级,据此计算结果提出了阿司匹林的热解机理,按此机理得到的理论计算值与实验结果一致;运用Freeman-Carroll、Kissinger和Ozawa三种方法分别计算了阿司匹林的热解动力学参数:活化能(E)、反应级数(n)和指前因子(A),其热解动力学方程为:dα/dt=4.74×1011犤exp(-(100.34±5.18)×103/RT)犦(1-α)2.8±0.3;用差示扫描量热法测定的该物质的熔点、摩尔熔化焓和摩尔熔化熵分别为(409.19±0.22)K、(29.17±0.41)kJ·mol-1和(71.09±1.06)J·mol-1·K-1.The mechanism of thermal decomposition of aspirin was studied by both thermogravimetry and Mayer bond orders calculated by Cerius2 software.The parameters of thermal decomposition kinetics for aspirin,such as activation energy (E),reaction order (n) and frequency factor (A) were obtained by thermogravimetry.The kinetic equation of thermal decomposition of aspirin is expressed as: dα /dt=4.74× 1011[exp(- (100.34± 5.18)× 103/RT)](1- α )2.8± 0.3 Melting point,molar enthalpy and entropy of fusion of aspirin were examined to be (409.19± 0.22) K,(29.17± 0.41) kJ· mol- 1 and (71.09± 1.06) J· mol- 1· K- 1,respectively,by means of DSC with a rising temperature program.The results obtained show that theoretical mass loss derived from Mayer bond orders of aspirin is in very good agreement with that obtained from thermogravimetry experiment.

关 键 词：阿司匹林 热解机理 热动力学 差式扫描量热法 药理学 

分 类 号：TQ460.1[化学工程—制药化工]