E-51环氧树脂固化反应中动力学转变

Shifting of the curing kinetics of E-51 epoxy resin

采用等温DSC法研究了E-51环氧树脂与4,4’-二氨基二苯基砜(DDS)体系的固化反应过程,并与已有固化模型拟合得到了170、180、190、200℃下的等温固化反应动力学的参数,根据决定系数R2确定了适合的固化模型。研究表明:当固化度小于40%时属于Kamal自催化模型;当固化度大于40%时属于n级固化模型,即固化反应由Kamal自催化反应向n级反应转变。

The cure reaction kinetics of E-51 epoxy resin and 4,4＇-diaminodiphenylsulfone（DDS） system was investigated by the isothermal DSC method,and isothermal curing kinetics parameters at 170,180,190,200℃ were obtained through fitting between the experimental data and the curing model.According to the values of coefficient of determination（R2） of the fitted data,a suitable curing reaction kinetic model was determined.The reaction process shows to be dominated by different mechanism at different stages of the E-51/DDS system curing process,when the cure degree is less than 40%,the curing system is Kamal autocatalytic reaction model;when the cure degree is more than 40%,the curing system is nth order reation model,with an initial autocatalytic reaction shifting into an nth order reaction as the reaction proceeding.