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Selective devulcanization of ground tire rubber by choline-based deep eutectic solvents for high-performance recycled materials
Liu Yang, Xuan Zhao, Sun Xinyu, Shuai Yuan, Lei Zhu
Vol. 19., No.8., Pages 783-795, 2025
DOI: 10.3144/expresspolymlett.2025.60
Corresponding author: Xuan Zhao

GRAPHICAL ABSTRACT

ABSTRACT

Waste tire rubber poses significant environmental challenges due to its non-biodegradability and complex crosslinkedvstructure. In this sense, this study aims to examine the utilization of deep eutectic solvents (DESs) in the desulfurizationvprocess of ground tire rubber (GTR). A range of hydrogen bond donors (HBDs), including ethylene glycol, malonic acid,vimidazole, toluene sulfonic acid, and urea, were combined with choline chloride, which serves as a hydrogen bond acceptorv(HBA), to synthesize deep eutectic solvents. Subsequently, these DESs are used in the modification of rubber devulcanizationvprocesses. Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and Horikx analysis werevused to confirm the occurrence of devulcanization. The studies confirmed that the devulcanization process was selective invnature, effectively reducing random chain scission while maintaining the integrity of the polymer. Furthermore, the vulcanizatesvobtained post-treatment demonstrated enhanced properties, including increased tensile strength, modulus, tear strength, hardness, and durability, with ethylene glycol-based DES (DES-E) exhibiting the most pronounced enhancements.


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Published by:

Budapest University of Technology and Economics,
Faculty of Mechanical Engineering, Department of Polymer Engineering