Synergism in the devulcanization of rubber in a closed vessel microwave using HNO3 and H2O2
Year: 2025
Type: article
Abstract: Waste rubber disposal causes considerable negative environmental impacts due to its increase worldwide, mainly in the automotive industry.Therefore, the search for technological solutions for rubber waste is a priority, and the first step in this material degradation is devulcanization due to its difficult degradation.This study evaluated rubber devulcanization using a closed vessel microwave digestion system with nitric acid (HNO 3 ) and hydrogen peroxide (H 2 O 2 ) through chemical characterization, aiming at verifying the synergistic effect between these oxidizing agents.Microwave irradiation was applied as a heating method to facilitate the chemical reactions, focusing on the synergism between HNO 3 and H 2 O 2 .Results showed that 5 M H 2 O 2 in combination with 1% HNO 3 , presented better results.A greater decrease in cross-link density was demonstrated as the concentration of H 2 O 2 increased (3.96•10 -5 ±1.99•10 -6 mol/cm 3 ), likewise, higher sulfates released (926.8±53.4mg/L), increased mass loss (12.184±1.06%),rubber surface fragmentation, and important variations in the C-S, C=O bands, showing better results when devulcanization is carried out in synergism between HNO 3 and H 2 O 2 .
Source: eXPRESS Polymer Letters
Authors: Cristian Valdés, Valentina Guzmán, Camila Ponce, Maribel Mamani, Juan Guevara, Claudia Vergara, Rodrigo Andler
Institutions: Catholic University of the Maule, Universidad Santo Tomás
Language: English
Subfield: Polymers and Plastics
Field: Materials Science
Domain: Physical Sciences
Open Access status: diamond
OpenAlex ID: W4409582074