Multi-component optimization in ENR composites using Taguchi-based statistical study: balancing curing agents, plasticizer, and silica filler

The performance of epoxidized natural rubber (ENR) composites is significantly influenced by the precise loading of essential components like curing agents, plasticizers, fillers, etc. This study utilizes the Taguchi method, a durable statistical approach to optimize the formulation of ENR composites by systematically adjusting the loadings of aminopropyl terminated polydimethyl siloxane (AP-PDMS), Hydroquinone (HQ), epoxidized soybean oil (ESO), and silica filler. The influence of these additives on the ENR composite’s mechanical and thermal properties was methodically investigated. An L9 (3^4) orthogonal array was designed to assess the impact of these elements on critical performance criteria like crosslinking density, hardness, tensile strength, elongation at break, tear strength, and thermal characteristics. The most influential elements and their ideal values were found using the signal-to-noise (S/N) ratio. The results demonstrate that when compared to the least performing composite, with optimized formulations, AP-PDMS and silica were the dominant factors in improving mechanical properties, achieving up to a ~ 1130% increase in tensile strength, ~ 295% enhancement in tear strength, whereas ESO positively influenced elongation at break and increased it by ~ 36%, highlighting its role in improving flexibility. Hydroquinone, functioning as a co-curing agent, affects crosslinking density, physical properties and thermal stability. The optimized formulation offers high-performance ENR composites for different applications. Unlike previous ENR composite optimizations, which primarily focused on conventional curatives or single-variable designs, this study his work provides a multi-parameter optimization strategy by integrating multiple additives simultaneously under a robust statistical framework, thereby minimizing experimental work. The optimized composite formulations provide a balanced improvement in mechanical integrity and flexibility.

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