The curing behavior of diglycidyl-4

5-epoxycyclohexane-1

2-dicarboxylate with m-phenylenediamine has been studied by using torsional braid analysis. It is shown that the whole curing processproceeds in two stages

that is

curing reaction at temperatures below 100℃ mainly occurs at the ali-phatic epoxy rings

whereas a rapid increase in reaction rate of the remaining cycloaliphatic epoxy ringoccurs only at temperatures above 130℃. Between the temperature range from 100℃ to 130℃

the"full reaction" of the aliphatic epoxy rings is approximated

while the reaction rate of the cycloaliphatic epoxy ring begins to increase gradually.The maximum glass transition temperature(Tg∞) of the system does not emerge before 220℃.The apparent activation energy is 13.2 kcal/mole.