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Updated: Aug 10, 2026
08:12
Depolymerizable Olefinic Polymers Based on Fused-Ring Cyclooctene Monomers
Published on: December 16, 2022
Degradable Alternating Copolymers With Strained Cyclobutane Backbones via Photocontrolled RAFT Polymerization
Xia Hu1, Hongsik Kim1, Lianqian Wu1
1Department of Materials, ETH Zurich, Zurich, Switzerland.
Angewandte Chemie (International Ed. in English)
|August 8, 2026
Summary
Researchers developed novel copolymers using reversible addition-fragmentation chain transfer (RAFT) polymerization of bicyclobutanes (BCBs) and other monomers. These advanced materials offer high thermal stability and unique mechanical degradability, paving the way for new polymer applications.
Area of Science:
- Polymer Chemistry
- Materials Science
- Organic Synthesis
Background:
- Controlled radical polymerization techniques enable precise polymer synthesis.
- Strained cyclic monomers offer unique backbone structures and properties.
- Visible-light-mediated polymerizations provide sustainable synthetic routes.
Purpose of the Study:
- To report a novel reversible addition-fragmentation chain transfer (RAFT) alternating copolymerization.
- To synthesize well-defined copolymers from 1,3-disubstituted bicyclo[1.1.0]butanes (BCBs) with various monomers.
- To investigate the properties of resulting polymers, including thermal stability and degradability.
Main Methods:
- Utilized RAFT polymerization under visible-light irradiation.
- Employed a chain transfer agent (CTA)-mediated photoiniferter process.
- Synthesized BCB monomers with specific electronic and steric tuning.
Main Results:
- Achieved high degrees of alternation and tunable molecular weights in copolymers.
- Demonstrated excellent end-group fidelity in the synthesized polymers.
- Obtained polymers with high thermal stability (decomposition temperature up to 429°C).
- Showcased highly efficient degradation of polymers under mechanical stimulation.
Conclusions:
- Developed a method for creating well-defined copolymers with strained cyclobutane backbones.
- The synthesized polymers possess a unique combination of high thermal stability and mechanical degradability.
- This work offers a pathway for designing advanced functional polymers with tailored properties.
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