Glass transition temperature-cure temperature-transformation (TgTT) diagram for EPY (R) epoxy system

摘要

The EPY (R) epoxy system applied for the production of machine foundation chocks was isothermally cured at varying cure temperatures and times. The thermal behavior during the curing of the system was monitored by means of the glass transition temperature (T-g) and conversion degree (alpha) measured using differential scanning calorimetry (DSC) and rotational viscometry (ARES). Also, the thermal decomposition was measured by thermogravimetry and differential thermal analysis (TG-DTA). The results were analyzed and summarized in the generalized phase diagram, as well as in the T-g-cure temperature-transformation (TgTT) cure diagram. The phase diagram has reference to the transformations (in liquid, ungelled glass, gelled glass and rubber state) encountered at time to gelation and vitrification. Whereas the TgTT diagram shows that there are three types of behavior related to the temperature of cure and makes a useful framework for understanding and analyzing the relations and interdependencies during the curing process of the epoxy system.