Effects of sulfur accelerators on the performance of EPDM/SBR blends

Accelerators are known to function via a complex reaction mechanism. Understanding the role played by accelerators in the vulcanization of elastomer blends is further complicated by differences in their solubilities in the elastomers which makeup the blend. In this study, blend properties were optimized by selecting accelerators with a shorter scorch time and a faster cure rate in the EPDM phase than in the SBR phase. Using the techniques described in this work, sulfur vulcanizates with compound properties comparable to those cured with a cure system composed of peroxide and sulfur coagent were obtained.