Monomer centred selectivity guidelines for sulfurated ring-opening copolymerisations

Title data

Stühler, Merlin R. ; Kreische, Marie ; Fornacon-Wood, Christoph ; Rupf, Susanne M. ; Langer, Robert ; Plajer, Alex:
Monomer centred selectivity guidelines for sulfurated ring-opening copolymerisations.
In: Chemical Science. Vol. 15 (2024) Issue 45 . - pp. 19029-19036.
ISSN 2041-6539
DOI: https://doi.org/10.1039/D4SC05858E

Official URL:

Abstract in another language

Sulfur-containing polymers, such as thioesters and thiocarbonates, offer sustainability advantages, including enhanced degradability and chemical recyclability. However, their synthesis remains underdeveloped compared to that of their oxygen-containing counterparts. Although catalytic ring-opening copolymerization (ROCOP) can provide access to sulfur-containing polymers, these materials often exhibit uncontrolled microstructures and unpredictable properties. A comprehensive model that elucidates the factors determining selectivity in these catalytic reactions is still lacking, despite its central importance for advancing these polymerizations into widely applicable methodologies. In this study, we investigate the factors that lead to selectivity in sulfurated ROCOP across various monomer combinations, including thioanhydrides or carbon disulfide with epoxides, thiiranes, and oxetanes. We find that unwanted by-products primarily arise from backbiting reactions of catalyst-bound alkoxide chain ends, which can be mitigated by (i) selecting monomers that form primary alkoxide of thiolate chain ends, (ii) maximizing ring strain in the backbiting step, and (iii) timely termination of the polymerization. By applying these strategies, the selectivity of the catalytic ROCOP can be controlled and we successfully synthesized perfectly alternating poly(esters-alt-thioesters) from various oxetanes and the highly industrially relevant ethylene oxide. Our study thereby shifts the focus for achieving selectivity from catalyst to monomer choice providing valuable mechanistic insights for the development of future selective polymerizations, paving the way for sulfurated polymers as potential alternatives to current commodity materials.

Further data

Item Type:	Article in a journal
Refereed:	Yes
Institutions of the University:	Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Chemistry > Junior Professor Polymers for Electrooptical and Sensory Applications > Junior Professor Polymers for Electrooptical and Sensory Applications - Juniorprof. Dr. Alex Johannes Plajer Research Institutions > Affiliated Institutes > Bavarian Polymer Institute (BPI) Faculties Faculties > Faculty of Biology, Chemistry and Earth Sciences Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Chemistry Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Chemistry > Junior Professor Polymers for Electrooptical and Sensory Applications Research Institutions Research Institutions > Affiliated Institutes
Result of work at the UBT:	Yes
DDC Subjects:	500 Science > 540 Chemistry
Date Deposited:	18 Jan 2025 22:00
Last Modified:	20 Jan 2025 06:12
URI:	https://eref.uni-bayreuth.de/id/eprint/91627