Effect of Tulbaghia violacea‐Derived Devulcanized Rubber on the Properties of Natural Rubber/Styrene‐Butadiene Rubber Blends

Abstract

Abstract The current study serves to demonstrate the potential utilization of devulcanized rubber produced using Tulbaghia violacea Harv. in a supercritical media. The devulcanized rubber, ranging from 5 to 35 wt% is incorporated into virgin natural rubber (NR)/styrene‐butadiene rubber (SBR) blends. The effect of devulcanized rubber addition is assessed by evaluating variations in the curing characteristics, physical attributes, morphologies, mechanical properties, and dynamic mechanical analysis of several vulcanized blends. The findings indicate a reduction in the blends' curing characteristics with an increase in devulcanized rubber proportion, except for minimum torque. Furthermore, the ultimate tensile strength, elongation at break, tear strength, and rebound resilience decrease, while the tensile moduli and stiffness exhibit an increase with an increase in devulcanized rubber proportion. The observed decline in mechanical property is associated with failure points identified through surface fracture imaging. Additionally, an increase in crosslink density and hardness aligned with the alterations in dynamic mechanical properties as the proportion of devulcanized rubber is increased. The study suggests that the rubber devulcanized with T. violacea Harv.—when blended with virgin NR/SBR blends—could be tailored for specific applications.

Keywords

• devulcanization
• devulcanized rubber
• pneumatic truck tire
• rubber properties
• rubber recycling
• Tulbaghia violacea