Correlation between vitrification temperatures of epoxyamine compounds andthe rates of their formation

The reaction of resorcinol diglycidyl ether with m-phenylenediamine at vitr eous polymer formation temperatures was studied by the method of kinetic ca lorimetry. Computer processing of the experimental kinetic curves showed th at, against the background of the exothermic reaction, an additional proces s with heat absorption occurred. The endothermic process began simultaneous ly with the vitrification of the reaction mixture. The finite degree of con version obtained from differential calorimetric curves did not correspond t o real process termination, because the reaction still proceeded at a low r ate. In solidified samples, the vitrification temperature (T-vit) obtained from the calorimetric curves did not equal its true value. The conclusion w as drawn that the current view according to which the temperature of isothe rmal solidification was stringently related to T-vit was physically unwarra nted.