Investigation of the effect of using devulcanized rubber in EPDM, NR, and EPDM/NR rubber compound recipes

Abstract

Waste rubber is one of the most important solid waste residuals today. Since the traditional disposal approaches of burning or storing them, especially end-of-life tires, were banned due to the production of toxic fumes and gasses that cause serious health problems and various environmental concerns, recycling waste rubber has gained importance in terms of sustainability. There are many studies in the literature on the recycling of waste rubber. Devulcanization is one of the hot spots in waste rubber recycling today. This work aimed to investigate the effects of using devulcanized waste rubber on the rheological and mechanical properties of the blends of natural rubber (NR) and ethylene-propylene-diene monomer (EPDM) rubber blends. A total of 38 parts per hundred (phr) of devulcanized rubber was introduced into rubber blends consisting of 100% NR, 80% NR/20% EPDM, and 100% EPDM. The effects of devulcanized rubber on the rheological and mechanical properties were studied by analyzing the obtained final products. The findings showed that devulcanized waste rubber functioned as a filler within the rubber compounds and improved some mechanical properties. The use of devulcanized rubber offered both economic benefits and environmental sustainability by promoting the efficient use of the limited resources. Additionally, the results were evaluated according to the SAE J200 M3BA510A14 standard, ensuring that the rubber blends met industry standards for durability and performance, particularly in demanding applications.