Cure kinetics of cyanate ester resin using microencapsulated dibutyltin dilaurate as catalyst

Dibutyltin dilaurate (DBTDL) catalyst-filled microcapsules (MCs) were used to catalyze the reaction of thermosetting cyanate ester (CE) resins. Dynamic differential scanning calorimetry (DSC) experiments were performed at multiple heating rates (β) to investigate the effects of the MC content (0.125, 0.25, and 0.5 %) on the cure kinetics of CE resins. The kinetic parameters of CE/MC systems, including activation energy (E _a), preexponential factor (A), and reaction order (n), were analyzed using the Flynn–Wall–Ozawa method, Kissinger method, Crane method, Ozawa isoconversional method, and Coats–Redfern method. The results indicate that, as the MC content increases, the reaction temperature of CE/MC system gradually shifts to low temperature owing to the increase of the DBTDL catalyst released from MCs under heating conditions. Compared to the unencapsulated DBTDL, the encapsulated DBTDL can decrease the E _a, A, and the reaction rate constant of CE resins due to the gradual release of DBTDL from MCs and the homogeneous dispersion of the released DBTDL in CE resins. The E _a, A, and the reaction rate constant of CE/MC systems are effectively adjusted by the MC content and heating process. The reaction orders for all CE/MC systems are close to 1. The reaction model of CE/MCs is considered as a two-dimensional nucleation (A ₂).