Title: initializer
Long Title: IUPAC Gold Book - initializer
DOI: 10.1351/goldbook.08957
Status: current

Definition
Starting initiator or transfer agent in reversible-deactivation polymerization (RDP).

Example
A starting alkoxyamine initiator in aminoxyl-mediated radical polymerization (AMRP), a starting alkyl halide initiator in atom-transfer radical polymerization (ATRP) and a starting RAFT agent in RAFT polymerization.

Related Terms
- RAFT agent: https://goldbook.iupac.org//terms/view/08968
- RAFT polymerization: https://goldbook.iupac.org//terms/view/08935
- aminoxyl-mediated radical polymerization: https://goldbook.iupac.org//terms/view/08917
- atom-transfer radical polymerization: https://goldbook.iupac.org//terms/view/08924
- reversible-deactivation polymerization: https://goldbook.iupac.org//terms/view/08912
- transfer agent: https://goldbook.iupac.org//terms/view/08947

Source
- PAC, 2022, 94, 1093. 'Terminology for chain polymerization (IUPAC Recommendations 2021)' on page 1122 (https://doi.org/10.1515/pac-2020-1211)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/08957/html
- json: https://goldbook.iupac.org/terms/view/08957/json
- xml: https://goldbook.iupac.org/terms/view/08957/xml

Citation: Citation: 'initializer' 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.08957
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Accessed: 2026-06-22T01:32:13+00:00