Investigating UV light and ziram catalyst as alternative activators for sulfur-promoted benzoxazine curing

High-temperature curing is a major limitation for the widespread use of benzoxazine resins. This study explores two strategies to reduce curing temperatures using minimal sulfur content (1-5 wt%): ziram catalysis and light activation. Both approaches effectively promoted curing at lower temperatures compared to traditional methods. The ziram-activated system achieved an activation energy as low as 83 kJ/mol, while the UV-activated system reached 63 kJ/mol. Furthermore, the UV-activated sulfur system exhibited improved thermal stability, particularly for cresol-based benzoxazines. The curing processes of monomers with catalysts were traced using various techniques, including nuclear magnetic resonance (NMR), Fourier-transform infrared (FT-IR), along with differential scanning calorimetry (DSC).