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Updated: Sep 10, 2025
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Depolymerizable Olefinic Polymers Based on Fused-Ring Cyclooctene Monomers
Published on: December 16, 2022
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Monomer-Dependent Selectivity in Sulfur-Containing Ring-Opening Copolymerisation: Bimetallic Catalysis for Predictive
Bhargav R Manjunatha1, Mani Sengoden2, Merlin R Stühler1
1Makromolekulare Chemie, Universität Bayreuth, Universitätsstraße 30, Bayreuth, 95447, Germany.
Angewandte Chemie (International Ed. in English)
|August 26, 2025
Summary
Researchers developed new methods for creating sulfur-containing polymers using ring-opening copolymerization. Carbonyl sulfide (COS) and PhNCS monomers show promise for designing degradable, high-performance materials.
Area of Science:
- Polymer Chemistry
- Materials Science
- Organic Synthesis
Background:
- Sulfur-containing polymers offer unique properties like degradability and high refractive indices.
- Developing precise synthetic strategies and understanding monomer selection for these polymers remain significant challenges.
Purpose of the Study:
- To comprehensively evaluate sulfurated ring-opening copolymerizations (ROCOP) under unified conditions.
- To identify optimal sulfur monomers and catalyst systems for controlled polymer synthesis.
Main Methods:
- Utilized a single heterobimetallic Cr(III)/Rb(I) catalyst platform for ROCOP.
- Investigated diverse heteroallene/epoxide systems, including carbonyl sulfide (COS), PhNCS, thioanhydrides, and CS2.
- Analyzed monomer reactivity, selectivity, and byproduct formation.
Main Results:
- Demonstrated synergistic catalyst performance in controlling activity and selectivity.
- Identified carbonyl sulfide (COS) as the most promising monomer for perfectly alternating copolymers under mild conditions.
- PhNCS emerged as a viable alternative, while thioanhydrides and CS2 showed lower selectivity and byproduct formation.
Conclusions:
- Established the first predictive framework linking sulfur monomer identity to selectivity and reactivity in ROCOP.
- Enabled the rational design of degradable, sulfur-rich polymers with tailored properties.
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