摘要
采用DSC研究了以双氰胺/取代脲为潜伏型中温固化体系的三官能团环氧树脂TDE-85的固化反应动力学,探讨了反应机理并确定了最佳的固化工艺参数。结果表明,固化温度<140℃时,受扩散效应和双氰胺在环氧树脂中溶解速率的影响,体系的等温固化行为与自催化模型存在偏差;固化温度>150℃后,体系的等温固化行为可用自催化反应模型很好地描述,其表观活化能为86.33 kJ/mol,指前因子为2.68×1010,总反应级数(m+n)为2～3。综合变温DSC和等温DSC的实验结果,可确定体系的最佳固化工艺条件为:120℃下预固化1 h后再升温至150℃保温1 h。
The curing kinetics of trifunctional epoxy TDE - 85 moderate - temperature curing system using dicyan- diamide/substituted urea as latent was studied by DSC. The reaction mechanism was investigated and the optimum curing process parameters were determined. The results showed that the isothermal curing behavior of the system wasnt in accord with autocatalytic kinetics model due to the influence of diffusion effect and dissolution rate of DICY in epoxy resin when curing temperature was lower than 140 ℃. When curing temperature was over 150 ℃, isothermal curing behavior could be described well by autocatalytic kinetics model. The apparent activation energy, pre - exponential factor and total reaction grades （m ＋ n） was 86. 33 kJ/mol, 2. 68 × 10 10 and 2 -3, respectively. The optimal curing process 120 ℃/1 h ＋ 150 ℃/1 h was determined on the results of non - isothermal and iso- thermal DSC.
出处
《热固性树脂》
CAS
CSCD
北大核心
2013年第3期10-14,共5页
Thermosetting Resin
