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Updated: Jun 2, 2026
08:12
Depolymerizable Olefinic Polymers Based on Fused-Ring Cyclooctene Monomers
Published on: December 16, 2022
Chemically Circular Poly(Orthoester) Elastomers Synthesized by Halogen-Bond Donor Catalyzed Cationic Ring-Opening
Zohaib Siddiqi1, Brooks A Abel1,2
1Department of Chemistry, University of California, Berkeley, California, USA.
Angewandte Chemie (International Ed. in English)
|May 31, 2026
Summary
Researchers developed a controlled synthesis for poly(orthoesters), a class of biodegradable polymers. This breakthrough enables sustainable and circular materials through controlled polymerization and chemical recycling.
Area of Science:
- Polymer Chemistry
- Materials Science
- Sustainable Chemistry
Background:
- Synthetic polymers are vital but pose environmental challenges.
- Next-generation polymer synthesis needs novel monomer classes.
- Poly(orthoesters) are underexplored biodegradable and recyclable polymers.
Purpose of the Study:
- To develop a molecular weight-controlled synthesis for poly(orthoesters).
- To overcome synthetic challenges in cationic ring-opening polymerization.
- To establish poly(orthoesters) as a sustainable and circular material platform.
Main Methods:
- Cationic ring-opening polymerization of spiro orthoesters.
- Utilized a tridentate halogen-bond donor catalyst for polymerization control.
- Investigated mechanistic pathways for molecular weight control and deactivation.
Main Results:
- Achieved molecular weight-controlled synthesis of poly(orthoesters).
- Demonstrated reversible-deactivation via anion-binding by the catalyst.
- Observed immortal-like polymerization behavior with precise molecular weight control.
- Confirmed controlled degradation and chemical recycling to monomer.
Conclusions:
- Established a robust method for synthesizing poly(orthoesters) with controlled molecular weights.
- Poly(orthoesters) exhibit tunable properties, controlled degradation, and chemical recyclability.
- This work positions poly(orthoesters) as a key platform for sustainable and circular materials.
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