基于变活化能模型的T800/环氧树脂预浸料固化反应动力学研究

为了深入了解某新型高温固化T800/环氧树脂预浸料的固化行为,借助差示扫描量热仪(DSC),采用非等温DSC法研究了T800/环氧树脂预浸料的固化反应过程。基于唯象模型,系统研究了该预浸料的固化反应特征温度及固化动力学参数,确定该预浸料中环氧树脂的固化反应动力学模型为自催化模型。采用等转化率法,分析了预浸料中环氧树脂的反应活化能随固化度的变化情况,结果表明在整个固化反应过程中,树脂固化反应活化能变化较大,传统模型法基于全固化过程活化能不变的假设无法准确描述该固化反应。采用变活化能自催化模型,利用粒子群全局优化算法,得到了T800/环氧树脂预浸料的固化动力学方程,结果表明该模型能较好地描述实验现象,可为进一步研究该预浸料的热力学性能及其成型过程中的质量控制提供理论基础。

STUDY ON THE CURE KINETICS OF T800/EPOXY RESIN PREPREG BASED ON ACTIVATION ENERGY VARIABLE MODEL

To further analyze the curing behavior of a new kind of high temperature curing T800/epoxy resin prepreg, dynamic differential scanning calorimetry (DSC) method was carried out to investigate the cure behavior of T800/prepreg.The characteristic temperatures and cure kinetics parameters of the prepreg were systematically investigated based on phenomenological model, and the cure reaction kinetic model of the epoxy resin was determined to be the autocatalytic model.The relation of activation energy versus degree of cure was obtained by iso-conversional method for the epoxy resin in prepreg.The results show that the reaction activation energy of epoxy resin in the prepreg changed significantly with increasing degree of cure during the whole curing process.Thus, the curing model based on the assumption that the activation energy was a constant during the whole curing process could not describe this curing reaction accurately.Therefore, an activation energy variable autocatalytic kinetic model and particle swarm global optimization algorithm were used to obtain the cure kinetic equation of T800/epoxy resin prepreg.The results show that this model achieves a good correlation with the experiment data, hence providing a theoretical base for further study on thermodynamic properties and enables the quality control during the curing process for the prepreg.