Effect of Thermal Aging on the Tensile and Tribological Properties of Pineapple Leaf Fiber‐Reinforced Natural Rubber Composites Incorporating Multiwalled Carbon Nanotubes

ABSTRACT Thermal aging of natural rubber (NR) composites is the long‐term, irreversible alterations in the composition, morphology, and structure caused by exposure to temperatures normally encountered in service. This has a significant impact on the tensile, wear, and friction properties of the composites. This study aims to investigate the effect of thermal aging on the tensile, wear, and frictional properties of pineapple leaf fiber‐reinforced NR composites with added multiwalled carbon nanotubes (MWCNTs). The variations in tensile and wear properties were monitored for 2, 4, and 6 days of aging at 60°C and 80°C. The morphologies of the tensile‐fractured and worn surfaces were investigated using scanning electron microscopy (SEM). Early in aging, the tensile strength and modulus initially increased, then decreased. The frictional force, coefficient of friction (COF), and specific wear rate gradually increased with aging duration and temperature. After the inclusion of MWCNTs, the tensile strength and COF increased up to 3.21 MPa and 0.94, respectively, under aging conditions of 80°C for 6 days. SEM analysis provided evidence that thermal aging exposure can induce surface cracks, leading to a reduction in the tensile properties of the composites. These findings provide valuable insights into material design for a wide range of applications.