Towards Sustainability: Fiber Architectural, Interfacial Behaviorism, and Topographical Relationship in Sisal Fiber Reinforced Butadiene Rubber Composites for Commodity Rubber Goods

Researchers are increasingly using biocomposites in engineering to reduce their environmental impact, with cellulosic fibers as the primary natural fiber source. These fibers and their composites offer many benefits but also have drawbacks, especially regarding environmental factors. For the first time, the study examined the reinforcing effects of short sisal fibers (4.0-5.5 mm) in butadiene rubber (BR). These fibers were combined with the BR matrix and vulcanized to create flexible composite sheets. Standard techniques, such as tensile testing, hardness (Shore A) measurements, water absorption behavior, Payne effect study, abrasion resistance study, aspect ratio study, and swelling behavior, were used to assess the physico-mechanical properties. The BRSF30 composite demonstrated substantial enhancements in mechanical properties, with tensile strength increasing by 306.02%, hardness (Shore A) rising by 32%, and modulus of toughness improving by 45.28% compared to the pristine (BRSF0). Notably, the final decomposition temperature of BRSF30 also increased by 3.28% relative to the pristine compound (BRSF0). Morphological studies of cryofactured composites using scanning electron microscopy (SEM) provided detailed insights into fiber-matrix interactions and fiber pull-out at the fractured surfaces, while atomic force microscopy (AFM) demonstrated superior dispersion of the fibers in BRSF30 composite compared to BRSF0 and BRSF50. Fourier transform infrared spectroscopy (FTIR) was used to analyze chemical structure variations in samples. Efficient crosslinking in BRSF30 creates a 3D network within the rubber matrix, reducing polymer chain mobility and limiting moisture ingress to 6.05%. The crosslink density of BRSF30 increased by 67.11% compared to the pristine compound (BRSF0). Additionally, the rubber process analyzer (RPA) illustrated the Payne effect within the composites, showing a decrease in storage modulus with increasing strain amplitude. The BRSF30 composite showed a reduction in abrasion volume loss of approximately 50.41% and an increase in abrasion resistance of about 102% compared to the pristine compound. The BRSF30 composite exhibited an optimal aspect ratio of 15.94±0.02, and the soil burial and environmental durability test showed negligible weight loss and no significant color change over 15 days. The newly developed sisal fiber–BR composite may have potential applications as commodity rubber goods.