Chemical upcycling of complex PET waste: Upcycling of milder reaction conditions and use for polyurethane as added-value product
Year: 2025
Type: article
Abstract: This study presents an efficient chemical upcycling route for complex poly(ethylene terephthalate) (PET) waste, including post-consumer bottles, thermoform PET, and the glycolysed monomer bis(2-hydroxyethyl) terephthalate (BHET), transforming them into liquid polyols for the synthesis of polyurethanes. The strategy is based on a catalysed solvolysis using ethylene carbonate (EC) as both a reagent and solvent, operating under mild conditions and at atmospheric pressure. A systematic screening demonstrated that caesium carbonate (Cs 2 CO 3 ) is more efficient catalyst than KOH, as it minimises the hydrolysis of carbonate groups, thereby yielding polyols with a higher content of these valuable units. Kinetic studies revealed the critical importance of reaction time and the transition from a heterogeneous to a solvated and highly swollen polymer state. The resulting polyols, with controlled molecular weights in the range of 1000–2500 g/mol —appropriate for use as soft segments— were successfully employed in the synthesis of polyurethanes. The final materials exhibited high molecular weights and thermal properties that correlate with the chemical composition of the precursor polyol, validating this methodology as a versatile and sustainable alternative to advance towards a circular economy.
Authors: Miriam Paola Barrera Nava, María Dolores de Dios Caputto, Rodrigo Navarro, Alberto Fernández Torres, Antonio Martínez-Richa, Ángel Marcos-Fernández
Language: English
Subfield: Polymers and Plastics
Field: Materials Science
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $4,190
Funders: Comunidad de Madrid, Ministerio de Ciencia, Innovación y Universidades, European Commission, Consejo Nacional de Ciencia y Tecnología, Ministerio de Economía y Competitividad, Ministerio de Ciencia e Innovación, Universidad de Guanajuato, Consejo Superior de Investigaciones Científicas, H2020 European Research Council
OpenAlex ID: W4417122945