[en] The inherent skeletal and thermal features to forge polymers by step-growth polymerization are conflicting with any depolymerization strategies via cascade back-biting reactions that necessitate adequate ceiling temperature, spacers, and functionalities to create cyclic compounds. Here, we report the edition of step-growth poly(carbonate-urea)s and poly(carbonate-amide)s that are depolymerized on demand into their native precursor or added-value offspring oxazolidinones, together with a hemiacetal cyclic carbonate. The unprotected in-chain secondary amide or urea functionalities of the polymers trigger their degradation via cascade ring-closing events upon a thermal switch (from 25 to 80 °C) in the presence of an organic base as a catalyst. Although most studies are realized in solution for understanding the deconstruction process, the polymers are also fully degraded in 2 h in neat conditions without any catalyst at 150 °C. At 80 °C, the organic base is required to accelerate the process. On the road to sustainability and circularity, we validate the concept by exploiting monomers designed from waste CO2 and upcycled commodity plastics. Ultimately, these polymers are selectively depolymerized from plastic mixtures composed of commodity poly(ethylene terephthalate) and polycaprolactone, offering new options for recycling plastic waste mixtures while delivering high-value-added chemicals.
Research Center/Unit :
Complex and Entangled Systems from Atoms to Materials (CESAM) Research Unit Center for Education and Research on Macromolecules (CERM)
Disciplines :
Materials science & engineering Chemistry
Author, co-author :
Siragusa, Fabiana ; University of Liège (ULiège), Complex and Entangled Systems from Atoms to Materials (CESAM) Research Unit, Center for Education and Research on Macromolecules (CERM), Belgium ; Université libre de Bruxelles (ULB), Laboratoire de Chimie Organique, Service de Chimie et Physico-Chimie Organiques, Belgium
Demarteau, Jérémy; University of the Basque Country, POLYMAT, Donostia/SanSebastian, Spain
Habets, Thomas ; University of Liège (ULiège), Complex and Entangled Systems from Atoms to Materials (CESAM) Research Unit, Center for Education and Research on Macromolecules (CERM), Belgium
Olazabal, Ion; University of the Basque Country, POLYMAT, Donostia/SanSebastian, Spain
Robeyns, Koen ; Université Catholique de Louvain (UCL), Institute of Condensed Matter and Nanosciences, Belgium
Evano, Gwilherm ; Université libre de Bruxelles (ULB), Laboratoire de Chimie Organique, Service de Chimie et Physico-Chimie Organiques, Belgium
Mereau, Raphael ; University of Bordeaux, CNRS, Institute of Molecular Sciences, Talence, France
Tassaing, Thierry; University of Bordeaux, CNRS, Institute of Molecular Sciences, Talence, France
Grignard, Bruno ; Université de Liège - ULiège > Complex and Entangled Systems from Atoms to Materials (CESAM)
Sardon, Haritz ; University of the Basque Country, POLYMAT, Donostia/SanSebastian, Spain
Detrembleur, Christophe ; University of Liège (ULiège), Complex and Entangled Systems from Atoms to Materials (CESAM) Research Unit, Center for Education and Research on Macromolecules (CERM), Belgium
Language :
English
Title :
Unifying Step-Growth Polymerization and On-Demand Cascade Ring-Closure Depolymerization via Polymer Skeletal Editing
Publication date :
01 June 2022
Journal title :
Macromolecules
ISSN :
0024-9297
eISSN :
1520-5835
Publisher :
American Chemical Society
Volume :
55
Issue :
11
Pages :
4637-4646
Peer reviewed :
Peer Reviewed verified by ORBi
Funders :
FWO - Fonds Wetenschappelijk Onderzoek Vlaanderen EU - European Union F.R.S.-FNRS - Fonds de la Recherche Scientifique EOS - The Excellence Of Science Program
Funding text :
The authors from ULiege thank the “Fonds National pour la Recherche Scientifique” (F.R.S.-FNRS) and the Fonds Wetenschappelijk Onderzoek–Vlaanderen (FWO) for financial support in the frame of the EOS Project No. O019618F (ID EOS: 30902231). The authors from UPV/EHU thank the Ministry of Spain for the EUR2020-112080 financial support. FNRS is also acknowledged for financing the COSwitch project. This project has received funding from the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska–Curie Grant Agreement No. 955700. C.D. is FNRS Research Director and thanks FNRS for financial support. 2
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