Characterization of New Rubber Compounds with Incorporation of Recycled Rubber Powders

Abstract:

The global growth of discarded end-of-life tires (ELT) is leading to a significant challenge of waste management. Many of these tires are incinerated or exported to countries with less stringent environmental regulations, exacerbating pollution and wasting resources. Until now, the main destinations for recycled rubber have been flooring, rubberized pavements, infill for synthetic turfs and moulded goods. The increasing necessity for the industry to adopt more sustainable products and processes by incorporating recycled materials, needs to be supported by innovative solutions. The present paper introduces a recycled rubber material, characterized by different certified laboratory tests performed to evaluate the mechanical and physical performance of a virgin rubber compound combined with different content levels of rubber powders derived from ELT, and with different particle sizes and production methods. There is extensive research on the ELT management systems and the various methods for recycling rubber from end-of-life tires, but limited studies on the impact of particle size and the influence of content of recycled rubber powders, added in new rubber compounds suited for performance-demanding applications. Based on the laboratory test results and the case study presented in this paper, it was possible to conclude that this recycled material can be incorporated into new rubber compounds, without compromising the performance. Numerous studies examine methods for recycling rubber from end-of-life tires, assessing their progress and limitations. Some focus on well-documented processes such as reclaiming, devulcanization, and surface modification, while others explore long-studied applications like rubberized concrete and rubber-modified asphalt. There is limited available information and published studies on the influence of particle size and content levels of recycled rubber powders that can be incorporated into new rubber compounds, for various applications such as new tires, conveyor belts, gaskets and profiles.

• Periodical: Materials Science Forum (Volume 1169)
• Pages: 73-78
• DOI: https://doi.org/10.4028/p-M7cPLX
• Online since: November 2025
• Authors: Nuno Soares Domingues, Luís Monteiro Gonçalves*
• Keywords: Ambient Grinding, Circular Economy, Cryogenic, ELT, End of Life, Innovative Materials, MRP, Polymer, Recycled Rubber Powder, Sustainable Development, Tyre, Waste Tire

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