Thermosetting reactions: Thermochemical reactions of triallyl cyanurate and triallyl isocyanurate

Triallyl cyanurate (TAC) and triallyl isocyanurate (TAIC) are thermosetting monomers with interesting interrelations: Calorimetry and infrared spectrophotometry were used to investigate the influence of atmosphere and initiator on the thermal events. The large extents of reaction observed during polymerization of TAC and TAIC are attributed to the formation of intramolecular rings. The higher conversions obtained with TAC are attributed to the extra length and flexibility of its allyl groups. Isomerization of poly(TAC) to poly(TAIC) is described as a three-step process: depolymerization of poly(TAC) to form monomeric TAC, isomerization of TAC to TAIC by a Claisen rearrangement, and repolymerization of the TAIC to poly(TAIC).