酚醛树脂固化的非模型拟合动力学研究

根据不等温差示扫描量热曲线,采用非模型拟合动力学法对酚醛树脂的固化动力学进行了研究。基于Fried-man,Flynn-Wall-Ozawa和Kissinger-Akahira-Sunose 3种模型计算得到了固化速率及活化能与固化度的关系,进而对此树脂体系的固化反应阶段及固化行为进行了分析,并对等温固化行为进行预测。结果表明,固化反应逐渐从自催化反应机理转变为n阶反应机理,与模型拟合法研究的结果基本吻合。对Friedman,Flynn-Wall-Ozawa,Kissinger-Akahira-Sunose 3种动力学方法进行比较发现,3种方法都显示了较好的拟合结果。其中,Flynn-Wall-Ozawa和Kissinger-Aka-hira-Sunose两种方法的结果十分接近,并能对固化行为进行准确地反映。

Model-free Kinetic Study of Phenol Formaldehyde Resin Cure

The curing behavior of novolac type phenolic resin was studied through differential scanning calorimetry(DSC) using model-free(isoconversion) kinetic methods.In the model-free kinetic study,Friedman,Flynn-Wall-Ozawa,and Kissinger-Akahira-Sunose methods were used to calculate the curing activation energy.The dependence curve of activation energy on conversion and the piecewise model fitting results both displayed a change in the kinetic reaction mechanism from the autocatalytic to n-order regime.According to the isothermal prediction results,the model-free kinetic methods show excellent prediction ability.Also,Flynn-Wall-Ozawa and Kissinger-Akahira-Sunose methods were found to show similar results in analyzing the curing behavior of this novolac resin.