新型磁性聚苯胺复合材料的热分解机理研究

Research on the Thermal Decomposition Mechanism of New Magnetic Polyaniline Composite

摘要: 采用热重–差热联用分析(TG-DTA)技术和热重红外(TG-FTIR)联用系统研究了新型磁性聚苯胺壳聚糖材料在氮气气氛中的热分解过程和非等温热分解机理及动力学。TG-DTA分析表明复合材料在190℃~460℃之间发生热分解反应，且分为两个阶段，第一阶段为190℃~380℃，第二阶段为400℃~460℃。运用MKN法、Coats-Redfern法和唐万军法对复合材料的非等温动力学数据进行分析，得出了热分解反应的机理函数、动力学参数、以及两步分解反应的活化能E和lnA。第一步分解的活化能为E = 113.9281 kJ∙mol⁻¹，指前因子为lnA = 20.705，动力学表达式为lnA = 4.95373E + 7.43443；第二步分解活化能为E = 184.578 kJ∙mol⁻¹，指前因子为lnA = 33.95，动力学表达式为lnA = 5.09915E + 5.61035。

Abstract: The thermal decomposition process and non-isothermal decomposition kinetic of Magnetic polyaniline chitosan were studied by the Differential Thermal Analysis (DTA), Thermogravimetric Analysis (TG) and TG-FTIR. It was demonstrated that the thermal decomposition temperature of magnetic polyaniline chitosan was in the range of 190˚C~460˚C, which was divided into two stages. The first stage was 190˚C~380˚C, and the second stage was 400˚C~460˚C. The mechanism function and kinetic parameters of non-isothermal decomposition of the two steps were discussed, and the E and lnA of the process were obtained from the analysis of TG-DTA curves by MNK, Coats-Redfern and Tang Wanjun methods. The first step activation energy was E = 113.9281 kJ∙mol⁻¹, the pre-exponential factor was lnA = 20.705, and the kinetic expression was lnA = 4.95373E + 7.43443. The second step of the activation energy was E = 184.578 kJ∙mol⁻¹, the pre-exponential factor was lnA = 33.95, and the kinetic expression was lnA = 5.09915E + 5.61035.