Kinetic Method by Using Calorimetry to Mechanism of Epoxy-Amine Cure Reaction

The thermokinetic behavior of the reaction between phenyl glycidyl ether and aniline closely resembles the analogous diepoxy diamine cure reaction in that the reactants are assembled before bond-breaking step occurs, and does not proceed through free reacting groups. The mechanism of the reaction between phenyl glycidyl ether and aniline in solventless system involves in addition to mechanism of the epoxy ring opening, structure changes accompanied by phase separation related to the self-aggregation. In an attempt to obtain further information about the reaction mechanism, the DSC heating runs of the reacted samples have been examined. These results suggest that the observed endothermic peaks are associated with additional ordering. The latter takes place only at lower temperature than reaction temperature. Since the rate constant k2 values for autocatalysed reaction follow of Arrhenius behavior, it is possible to calculate the activation energy, which is E=51 kJ mol-1. Analysis of the kinetic experiments demonstrates that the heat of reaction that are detected in kinetic measurements provide correct information about the mechanism of the process.