Curing reaction of elastomers with triazine thiols and sulfen amides

摘要

AbstractCuring reaction of elastomers with triazine thiols and sulfen amides in the presence of ZnO and stearic acid was investigated for curing parameters and curing mechanism. The curing parameters such as curing rate, induction period, and curing efficiency were influenced by the pKa of thiol groups in triazine thiols and amines corresponding in sulfen amides, by the steric hinderance of 6‐substituted groups in triazine thiols and on amino groups in sulfen amides, by the molar ratio of sulfen amides to triazine thiols, and by the reacting positions and the properties of elastomers. Triazine thiols acted as curing agents. Sulfen amides played two important roles in curing elastomers with triazine thiols. They gave poly(triazinyl disulfide) which is a curing precursor. Curing activators are formed in the reaction of the precursors, sulfen amides, and ZnO. The activators react with elastomers to give crosslinks, pendants and triazine dithiols or triazinyl disulfide oligomers. The pendants react with sulfen amides to give the crosslinks. The triazine thiols or triazinyl disulfide oligomers react with sulfen amides to reproduce the curing precursors. The structure of crosslinks is estimated to