High-temperature and ageing properties of high-crystalline TOR-filled SBR vulcanizates

The influence of a co-cross-linkable processing aid, Trans-polyoctenylene (TOR), on hightemperature stress-strain properties and ageing of filled styrene butadiene rubber (SBR) vulcanizates, was studied. Three different cross-linking systems, conventional (CV), semiefficient (SEV) and efficient (EV), with respect to SBR were included. A linear regression equation has been obtained between vulcanizate modulus (200%), TOR dosage and sulphur/accelerator ratio at different test temperature. A similar equation has also been found with tensile strength at 120 °C. Thermal analysis, Fourier transform-infrared spectroscopy and a few solid-state ¹³Carbon nuclear magnetic resonance spectroscopic techniques were performed to get insight into the structural changes that occur between TOR and SBR during cross-linking. A plausible mechanism of the interaction between TOR and SBR has been suggested. Based on the property retention of the vulcanizates at room as well as at high working temperature, an optimization of properties between the CV and EV systems has been attempted by the modification of the CV system using TOR.