Effect of Cyclohexyl Thiophthalimide on NR Vulcanization Accelerated by Thiocarbamyl Sulfenamide-Dibenzothiazyl Disulfide System

Abstract

Abstract Investigations have been carried out on the effect of CTP on thiocarbamyl sulfenamides, either alone or in combination with MBTS, in the vulcanization of NR. It has been observed that CM, CP, CPTCD, OTCD, and CDB formed from various thiocarbamyl sulfenamides like OTOS, OTCS, and CTOS in the presence of CTP play a vital role in cure retardation. CM and CDB under the experimental conditions have been found to prolong the onset of cure, while CP, CPTCD, and OTCD reduce scorch time. The presence of a substituent on the carbamate N-atom of thiocarbamyl sulfenamides greatly influences cure retardation. OTOS and CTOS give rise to CM and CP respectively in the presence of CTP. OTCS, however, generates both CM and CP under the identical conditions and thus differs from OTOS and CTOS. CPTCD and OTCD formed from thiuramdisulfides have been shown to be poor and scorchy accelerators, and these, like CM and CP, play a significant role in cure retardation.