Synergism of novel thiuram disulfide and dibenzothiazyl disulfide in the vulcanization of natural rubber: curing, mechanical and aging resistance properties

Introduction Various combinations of synthesized thiuram disulfides (TD), namely Bis (N-phenyl piperazine) thiuram disulfide (PPTD) and Bis (N-ethyl piperazine) thiuram disulfide (EPTD) with mercapto benzothiazole disulfide (MBTS) are studied in natural rubber (NR) vulcanization. At the same time, we also revised the TDMBTS binary accelerator on the carbon black-filled NR system. An evaluation is prepared between the synthesized safe thiuram disulfides with the unsafe tetra methyl thiuram disulfide (TMTD) in the light of mechanical and aging resistance behavior to introduce non-carcinogenic rubber additives to vulcanization of rubber. Results Synthesized safe amine-based thiuram disulfides in combination with MBTS display strong synergism in the gum vulcanization. Higher concentration of thiuram disulfide in presence of MBTS (6:3 mM ratio) shows better results with respect to cure and physical properties. Conclusions In the specific concentration of 9 mM per hundred gram of rubber (6:3 mM ratio of TD to MBTS), however, PPTD-MBTS accelerated filled vulcanizates show utmost aging resistance behavior, but EPTD-MBTS accelerated filled stock spectacles show superior aging as well as mechanical properties as compared to that of TMTD-MBTS accelerated system.