Title: ring-opening polymerization
Long Title: IUPAC Gold Book - ring-opening polymerization
DOI: 10.1351/goldbook.R05396
Status: current

Definition
A polymerization in which a cyclic monomer yields a monomeric unit which is acyclic or contains fewer cycles than the monomer.

Note
If the monomer is polycyclic, the opening of a single ring is sufficient to classify the reaction as ring-opening polymerization.

Related Terms
- monomer: https://goldbook.iupac.org//terms/view/M04017
- monomeric unit: https://goldbook.iupac.org//terms/view/M04018
- polymerization: https://goldbook.iupac.org//terms/view/P04740

Source
- PAC, 1996, 68, 2287. 'Glossary of basic terms in polymer science (IUPAC Recommendations 1996)' on page 2308 (https://doi.org/10.1351/pac199668122287)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/R05396/html
- json: https://goldbook.iupac.org/terms/view/R05396/json
- xml: https://goldbook.iupac.org/terms/view/R05396/xml

Citation: Citation: 'ring-opening polymerization' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.R05396
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Accessed: 2026-06-30T20:49:57+00:00