Cyanuric chloride as a potent catalyst for the reduction of curing temperature of benzoxazines†
Cyanuric chloride (2,4,6-trichloro-1,3,5-triazine, TCT) was used as a catalyst to lower the ring opening polymerization (ROP) temperature of 1,3-benzoxazines. Dynamic scanning calorimeter (DSC) studies revealed that especially onset ROP temperatures were decreased as much as 75 °C for model benzoxazine compounds. The latent character of the catalyst was revealed spectroscopically by 1H NMR and FTIR, and TCT remained dormant at RT and activated after certain temperatures. Moreover, thermal stabilities of the TCT catalyzed polybenzoxazines were analyzed and compared to those of uncatalyzed counterparts. Thermal properties of the polymers obtained in terms of both initial degradation temperatures and char yields at 800 °C did not significantly change.