Abstract
6-dibutylamino-1, 3, 5-triazine-2, 4-bis (benzothiazolyl disulfide) (BT) was found to accelerate vulcanization of isoprene rubber at 135-170°C to give an improved vulcanizate with an ageing resistant and a reversion resistant property. Longer induction period and lower vulcanizing rate were observed in BT-accelerated vulcanization comparing with dibenzothiazyl disulfide (MBTS)-accelerated vulcanization. Similar accelerating property and ageing resistant property of the vulcanizate were observed on a combinated accelerating system of MBTS and 6-dibutylamino-1, 3, 5-triazine-2, 4-dithiol (DB), as BT was formed quantitatively with 1 mol of DB and 2 mols of MBTS. An ageing and a reversion resistant property of the vulcanizate with BT- or MBTS• DB-accelerator were supposed to be caused by the formation of dithiotriazine crosslink. Then, addition of DB with formed dithiotriazine crosslink, was found to be effective to prevent a reversion in the vulcanization with the conventional accelerator such as N-cyclohexyl-2-benzothiazol sulfenamide, N-oxydiethylene-2-benzothiazol sulfenamide or MBTS.
