利用时温等效原理修正的VARTM用双酚F型环氧树脂体系化学流变模型

Chemorheological model of a bisphenol-F epoxy resin system for VARTM processes with amendment of time-temperature equivalence

研究了A40/DDM/DMTDA复合体系固化双酚F型环氧树脂体系的化学流变特性,建立了该体系在恒温和动态升温情况下的双阿伦尼乌斯黏度模型。以100℃为参考温度,研究了该体系的时温等效效应,通过转换因子aT的偏移预测了其它温度点的黏度-时间曲线。并应用时温等效原理,修正了所建立的恒温模型,克服了原模型在黏度值较大时与实验值的偏差。修正后的双阿伦尼乌斯模型的黏度预测值在较大的黏度范围内与实验结果保持良好的一致性,可有效地预测VARTM工艺过程的黏度变化,为复合材料成型工艺模拟分析及工艺参数的确定奠定了基础。

The chemorheological behavior of A40/DDM/DMTDA curing bisphenol-F epoxy resin for vacuum assisted resin transfer molding（VARTM） was studied by means of isothermal and dynamical viscosity experiments.A dual-Arrhenius viscosity model was established and used to simulate the rheological behavior of the epoxy resin system.The time-temperature equivalence of the system was also analysed with the reference temperature 100℃,and the shift factor aT was calculated by the dual-Arrhenius equation which was then used to predict the viscosity data at other temperatures.It was also used to modify the established viscosity model in order to deal with certain differences between the experiments and calculations for the resin with high viscosity.The viscosity values estimated from the modified model under isothermal and dynamic condition are in good agreement with the experimental ones.The dual-Arrhenius model can be used to predict the chemorheology of different processing parameters of VARTM process,which can be useful for optimization of composite manufacturing processes.