Author, as appears in the article.: Marin-Genescà, M; García-Amorós, J; Mudarra, M; Vidal, LM; Cañavate, J; Colom, X
Department: Enginyeria Mecànica
URV's Author/s: Marín Genescà, Marc
Keywords: Vulcanization Tire rubber Scrap Relaxation Powder Morphology Conductivity Compatibility Blends Additives
Abstract: Ethylene propylene diene monomer (EPDM) is one of the most used polymers in the world. It is an elastomer, which means that the existing cross-linking between the main chains of the polymer created during the vulcanization process makes its recycling difficult. In this paper, a possible solution to this issue is studied. The devulcanization of EPDM is achieved by a thermomechanical process followed by microwave irradiation. These combined treatments suppress the cross-linking, yielding a material (EPDMd) that can be successfully blended to form composites. A common elastomer, styrene butadiene rubber (SBR), has been selected as the matrix. The new SBR/EPDMd composites can be useful as elastomeric dielectric materials and can contribute to the recycling of the discarded EPDM. To provide a better understanding of their microstructure and its relationship with their micro-and macroscopic behavior, samples containing 20 and 40% of EPDMd have been tested by thermogravimetric and dielectric analysis, focusing on variables such as the thermal properties of the blends, permittivity, electric modulus, conductivity, and activation energies. The results show interesting changes linked to the presence of EPDMd in the SBR matrix, such as the displacement of the beta dielectric relaxation toward higher frequencies. The correct integration between the two phases is confirmed by the absence of any Maxwell-Wagner-Sillars type relaxation in their dielectric behavior. The presence of additives in the EPDMd samples has an effect on the conductivity, mainly due to the conductive aluminum silicate present in the EPDMd, which acts toward increasing some key dielectric features like conductivity and permittivity and decreasing the insulation of the final SBR/EPDMd materials. The inclusion of EPDMd also affects the alpha relaxations (low frequencies) and suppresses the beta relaxations (high frequencies). The samples showed a non-Debye dielectric behavior. In short, a compact and well-integrated material with a dielectric behavior is created, which exhibits interesting differences from the reference SBR matrix. Finally, it is concluded that the compounds tested are suitable for applications as electrical insulators.
Thematic Areas: Química Interdisciplinar General chemistry General chemical engineering Engenharias ii Ciências agrárias i Chemistry, multidisciplinary Chemistry (miscellaneous) Chemistry (all) Chemical engineering (miscellaneous) Chemical engineering (all)
licence for use: https://creativecommons.org/licenses/by/3.0/es/
Author's mail: marc.marin@urv.cat
Author identifier: 0000-0002-7204-4526
Record's date: 2024-08-03
Papper version: info:eu-repo/semantics/publishedVersion
Link to the original source: https://pubs.acs.org/doi/10.1021/acsomega.2c08115
Licence document URL: https://repositori.urv.cat/ca/proteccio-de-dades/
Papper original source: Acs Omega. 8 (14): 12830-12841
APA: Marin-Genescà, M; García-Amorós, J; Mudarra, M; Vidal, LM; Cañavate, J; Colom, X (2023). Insights into the Structural and Dielectric Behavior of Composites Produced from EPDM Waste Processed through a Devulcanization Method and SBR. Acs Omega, 8(14), 12830-12841. DOI: 10.1021/acsomega.2c08115
Article's DOI: 10.1021/acsomega.2c08115
Entity: Universitat Rovira i Virgili
Journal publication year: 2023
Publication Type: Journal Publications