Exploring hybrid vulcanization system in high-molecular weight EPDM rubber composites: A statistical approach

Elastomeric compound development is a multi-objective optimization task, and it contains vulcanization packages that crosslink the matrix. The deciding factors for vulcanization systems are the nature of elastomer, service temperature, processing methods and vulcanizate properties. Accelerated sulfur and organic peroxide are examples of vulcanization systems; each has its advantages and shortcomings. The peroxide-based system shows a high level of temperature stability while its flexibility is inferior to sulfur vulcanization. This study is fine-tuning a hybrid vulcanization system containing a combination of ultra-fast accelerated sulfur and a peroxide system; it also optimizes the vulcanization package ratios concerning various rheological and vulcanizate properties with the help of the Taguchi method. Ethylene propylene diene rubber (EPDM) is chosen as the basic matrix due to its excellent viability and commercial application with both the vulcanization systems. The formulations are optimized to combine the advantages of both the vulcanization systems. The results indicate that the vulcanization is sulfur-driven, but peroxide influences by selecting the crosslink sites and type. The hybrid system uses more components, but proper optimization helps to reduce the quantity of vulcanization packages with an improvement in physio-mechanical properties; it also helps to reduce the discharge of carcinogenic accelerator by-products, such as nitrosamine.

Automated summary

This study fine-tunes and optimizes a hybrid vulcanization system containing a combination of sulfur and peroxide systems to combine their advantages, reduce the quantity of vulcanization packages, and minimize the discharge of carcinogenic by-products.