环氧基笼型倍半硅氧烷/4,4′-二氨基二苯砜体系的等温固化动力学

Isothermal Curing Kinetics of POSSER and 4,4'-Diaminodiphenylsulfone System

应用等温差示扫描量热法研究了4,4′-二氨基二苯砜(DDS)固化笼型倍半硅氧烷环氧树脂(POSSER)体系的反应动力学,测定了固化反应热,得出了不同温度下固化反应程度与反应时间、固化反应速率与反应时间的关系曲线,通过非线性拟合得到固化反应速率与反应程度的关系曲线。结果表明,固化反应在体系的玻璃化转变温度以上进行,等温固化反应遵从自催化反应机理,用Kamal方程可很好地描述不同温度下固化反应的自催化过程,拟合得到其反应动力学参数k1、k2、m、n,k1和k2对应的固化反应的表观活化能分别为79.67和59.84kJ/mol。

The isothermal curing kinetics of polyhedral oligomeric silsesquioxane-epoxy resin（POSSER） with 4,4′-Diaminodiphenylsulfone（DDS） as a curing agent was studied by means of differential scanning calorimetry（DSC ）. Analysis of DSC data indicates that an autocatalytic behavior occurred in the overall curing process, which can be described with the model proposed by Kamal that includes two rate constants, k1, k2, and two reaction orders, m and n. Rate constants k1 and k2 were observed to be greater when curing temperature increased. The overall reaction order, m ＋ n, is in a range of 1 - 1.6. The activation energies for k1 and k2 were 79. 67 kJ/mol and 59. 84 kJ/mol, respectively.