The Tear and Tensile Strengths of Silica Fly Ash Reinforced Natural Rubber Vulcanizate
Abstract
This study investigated the enhancement of tear and tensile strengths in natural rubber (NR) vulcanizates reinforced with silica fly ash. The focus was on evaluating the tear and tensile strengths of the composites to improve their performance across various industrial applications. NR, known for its elasticity and flexibility, is often reinforced with fillers to enhance its mechanical properties. Silica fly ash, a by-product of coal combustion, was utilized as a reinforcing agent due to its high silica content and fine particle size. A series of NR composites was prepared by incorporating silica fly ash at weight percentages ranging from 10 to 40 parts per hundred parts of NR (phr). The vulcanization process was optimized to ensure uniform dispersion of the fly ash particles within the NR matrix. The resulting vulcanizates were then subjected to standardized testing to measure their tear and tensile strengths. Results indicated a significant improvement in both tear and tensile strengths with the addition of silica fly ash, particularly at an optimal filler loading. The tear and tensile strengths of the NR vulcanizate with 30 phr silica fly ash (optimal filler loading) were 84.3 N/mm and 29.0 MPa, which were much higher than those of the tear and tensile strengths of the NR vulcanizate with no silica fly ash; 41.2 N/mm and 19.0 MPa, respectively. The 100% modulus, maximum, and delta torque for NR/silica fly ash vulcanizate were higher than those of unfilled NR vulcanizate. The study concludes that silica fly ash is a viable, cost-effective filler for NR, offering substantial improvements in mechanical properties. This finding not only promotes the use of industrial waste but also opens avenues for developing high-performance rubber composites for diverse applications.
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