Comparative study among TMTD, TBzTD, and ZBEC accelerators in isobutylene‐isoprene elastomer vulcanization

ABSTRACT Accelerators such as tetramethylthiuram disulfide (TMTD) are responsible for releasing nitrosamines, considered carcinogenic by international organizations. Tetrabenzylthiuram disulfide (TBzTD) and zinc dibenzyldithiocarbamate (ZBEC) are indicated as substituents of TMTD for not releasing noxious nitrosamines. Thus, the objective of this work was to compare the use of TMTD, TBzTD, and ZBEC accelerators in the production of isobutylene‐isoprene rubber compounds. It was evaluated the effect of TBzTD/mercaptobenzothiazole and ZBEC/N‐cyclohexyl‐2‐benzothiazolesulfenamide pairs in the rheological properties and the first pair achieved better results. Subsequently, it was evaluated compounds containing TBzTD and ZBEC accelerators separately. The experimental design data of the obtained maximum torque were correlated by an interpolation method (thin‐plate spline interpolation method). Physical–mechanical and thermodynamic measurements showed a decrease in the mechanical properties of TBzTD and ZBEC compounds. Thermogravimetric analysis did not indicate thermal differences between the compounds, Fourier transform infrared and swelling degree analyses corroborated the difference found in the crosslink densities of the compounds. © 2020 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48965.