双酚-S环氧树脂与间苯二胺固化反应动力学

CURING KINETICS OF BISPHENOL-S EPOXY RESIN AND m-PHENYLENEDIAMINE SYSTEM

用示差扫描量热法(DSC)研究了双酚-S环氧树脂(BPSER)与间苯二胺固化反应的历程。实验结果表明,固化反应主要分为2个阶段,前期由化学动力学控制,服从自催化机理,实验数据利用Kamal方程处理得到2个速率常数k1、k2及2个反应级数m、n,k1、k1值随反应温度的升高均呈增大的趋势,总反应级数m+n在2～2 5之间;反应活化能E1、E2分别为64 18kJ/mol和48 30kJ/mol。当反应程度达到60%左右后,由于交联程度增加,分子质量迅速增大,分子间扩散较慢,进入反应的第二阶段,主要由扩散作用控制固化速率。文章还讨论了该体系固化反应的分子机理,认为其经历了三分子的过渡态。

The cure kinetics of bisphenol-S epoxy resin(BPSER) and m-phenylenediamine were studied by means of differential scanning calorimetry(DSC).Analysis of DSC data indicated that course of the curing reaction was two stages,an autocatalytic behavior showed in the first stages of the cure.and was well described by the model proposed by Kamal including two rate constants,k_1 and k_2,and two reaction orders,m and n. The overall reaction order,m+n,was in the range 2～2.5.The activation energies for k_1 and k_2 were 64.18 and 48.30 kJ/mol,respectively.When the curing extent was about 60 percent,the molecular weight raised rapidly and diffusion control was incorporated to describe the cure in the latter stages.And the molecular mechanism of the curing system proceed through a trimolecular transition state initially for the reaction of epoxy compounds with amines.