The research findings on the mechanical properties of styrene-butadiene rubber (SBR) composites, particularly the impact of aging temperatures, have practical implications. To evaluate this effect, the study used a thermal aging test at various temperatures. The work developed SBR filled with several fillers, including kaolin, metakaolinite, zeolite Na-A, Al2O3, and synthetic zeolite Na-A/Al2O3 nanoparticles. A hybridization of SBR-filled synthetic zeolite Na-A/ Al2O3 composite was also created. The rubber mixer of two-roll mill was used to compound the material, with a filler loading of 1-5 phr. The mechanical properties of the elastomeric composites were determined before and after thermal-oxidative aging using an air-circulating oven. The respective composites were tested at varied aging times. A thermogravimetric analyzer (TGA) was used to measure thermal stability. The surface morphology of broken rubber composites was examined using a scanning electron microscope (SEM). Here, a comparative there is a comparative study of the Cross-link density estimations of cured SBR utilizing swelling and Mooney-Rivlin methods. The data from different comparison approaches yielded similar results, giving us considerable confidence in our research. Aging studies revealed that zeolite Na-A/Al2O3/SBR composite showed superior anti-aging properties in comparison to the other composite. The most effective, straightforward, and environmentally friendly technique for determining the Cross-link density of cured rubber was found to be the Mooney-Rivlin equation. Our research methods are more trustworthy because this process is based on mathematics and doesn't involve any hazardous chemicals or solvents. This study recommends using zeolite Na-A/Al2O3 as a cost-saving filler in SBR composites, which has practical implications for the industry.