Enhancing the tire performances of truck tire tread based on rubber compounds containing biobased processing oil by adjusting sulfur contents

Abstract

The mechanical properties of the rubber compounds such as modulus and tensile strength are very important to rubber products especially for tire applications. However, the presence of palm oil (PO) as a biobased processing oil in eco-friendly truck tire tread compounds encounters the low mechanical properties because PO molecules can consume sulfur as a curing agent. Therefore, this study focuses on incorporation of sulfur in varying contents on the properties of rubber compounds. The PO-added natural rubber compounds with different sulfur contents of 2.50, 2.75, and 3.00 parts per hundred rubber (phr) were prepared by taking the use of distillated aromatic extract (DAE) in natural rubber compound with 2.50 phr sulfur as a reference. The levels of crosslinking of the PO-added natural rubber compounds increased as the sulfur content increased, resulting in improvement in mechanical properties. Results showed that an additional incorporation of 0.25 phr sulfur content led to superior mechanical properties. Furthermore, PO improved the abrasion resistance by 38%, reduced heat buildup by 17%, and lowered tan δ at 60°C by 21%, when compared to the compound as a reference. Based on the results, the additional incorporation of sulfur not only improved the mechanical properties, but also enhanced tire performances especially low rolling resistance as reflected by energy-saving tires. Thus, PO can be an alternative to DAE in the natural rubber compounds for the application of truck tire treads when the additional incorporation of sulfur was applied.