The influence of composition of the dicyandiamide-asymmetric urea complex curing catalyst system on the thermal effect of the epoxy diane oligomer polymerization reaction

Abstract

To decrease the curing temperature of epoxy compositions at the use of dicyandiamide (DCDA) as a latent hardener, a curing catalyst system including, in addition to DCDA, asymmetric urea has been stud ied. The dependencies of parameters of chemical transformations in catalyzed epoxy compositions, such as thermal effects and conversion, on the composition of the complex curing catalyst system have been estab lished by the DSC and isothermal calorimetry techniques. It has been shown that the chosen optimal com position of the catalyst system allows curing the epoxy compositions in a two stage regime at lower tempera tures than in the case of the use of DCDA.