Term: living radical polymerization
https://doi.org/10.1351/goldbook.08914

Definition:
Radical polymerization in which chain termination and irreversible chain transfer are absent.

Notes:
1) Radical polymerizations, controlled radical polymerizations and reversible-deactivation radical polymerizations are not living radical polymerizations as there is a non-zero probability of chain termination.
2) The term living radical polymerization can be used to refer to a hypothetical radical polymerization that occurs without chain termination.
3) Use of the adjectives pseudo-living, quasi-living, 'living' (within quotation marks) or other terms that containing the word living to describe a radical polymerization with only some living characteristics is deprecated.

Example: Certain polymerizations conducted in confined media which only allow reactions of individual <em><a href="/terms/view/08966">propagating radicals</a></em>.

Example: Array

Related Term: reversible-deactivation radical polymerizations (http://doi.org/10.1351/goldbook.08916).
Related Term: controlled radical polymerizations (http://doi.org/10.1351/goldbook.08913).
Related Term: chain termination (http://doi.org/10.1351/goldbook.08946).
Related Term: chain termination (http://doi.org/10.1351/goldbook.08946).
Related Term: chain termination (http://doi.org/10.1351/goldbook.08946).

Source: PAC, 2022, 94, 1093. 'Terminology for chain polymerization (IUPAC Recommendations 2021)' on page 1103 (https://doi.org/10.1515/pac-2020-1211)

Citation: 'living radical polymerization' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.08914

License: The IUPAC Gold Book is licensed under Creative Commons Attribution-ShareAlike CC BY-SA 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) for individual terms.

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