Rubber 12 Sulfenamides Curing 8 Styrene 8 Styrene butadiene rubber 8 Sulfur 8 Vulcanization 8 Butadiene 6 Butadiene rubber 6 Cross-link densities 6 Crosslinking 6 Benzothiazoles 4 Cu-Re system 4 Cure kinetics 4 Cure temperature 4 Glass transition 4 Mechanical properties 4 Polybutadiene rubbers 4 Polybutadienes 4 Preparation method 4 Temperature dependence 4 Toluene 4 Torque curves 4 Vulcanization process 4 Vulcanized compounds 4 Activation energy 2 Blend 2 Blend composition 2 Blending 2 Blends 2