Curing and thermal degradation behavior of epoxy-based vitrimers

Epoxy with associative covalent adaptable networks (CANs), called vitrimer, is reported to be promising to realize the recyclable utilization. The typical epoxy vitrimers are synthesized from diglycidyl ether of bisphenol A and dicarboxylic catalyzed by triazabicyclodecene (TBD). The study on the curing and thermal degradation behavior facilitates in-depth understanding of the associative CANs. In this work, the effect of TBD on the curing and thermal degradation behavior is investigated via curing kinetics and thermal degradation performance analysis. The results reveal that the activation energy of curing reaction is increased as the amount of TBD is increased. EST-5 has an average activation energy of 70.1 kJ/mol, while EST-15 reaches as high as 75.1 kJ/mol. Especially, when the conversion is up to 50%, the activation energy shows an obvious increment. In addition, it has been demonstrated that TBD accelerates the thermal degradation of cured networks at lower temperature and increases the amount of volatiles during thermal decomposition. Pyrolysis volatiles of the cured vitrimer.image