Title: chain activation
Long Title: IUPAC Gold Book - chain activation
DOI: 10.1351/goldbook.08942
Status: current

Definition
Reaction of an activator with a dormant species to form a deactivator and a propagating species.

Notes
1) The activation and deactivation process may form part of a catalytic cycle. However, in general, the activator should not be called a catalyst.
2) Chain deactivation (in ATRP) is the reverse of chain activation (in ATRP).

Related Terms
- Chain deactivation: https://goldbook.iupac.org//terms/view/08943
- deactivator: https://goldbook.iupac.org//terms/view/08949
- dormant species: https://goldbook.iupac.org//terms/view/08952
- propagating species: https://goldbook.iupac.org//terms/view/08966

Source
- PAC, 2022, 94, 1093. 'Terminology for chain polymerization (IUPAC Recommendations 2021)' on page 1117 (https://doi.org/10.1515/pac-2020-1211)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/08942/html
- json: https://goldbook.iupac.org/terms/view/08942/json
- xml: https://goldbook.iupac.org/terms/view/08942/xml

Citation: Citation: 'chain activation' 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.08942
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Accessed: 2026-06-21T19:48:10+00:00