Title: auto-acceleration
Long Title: IUPAC Gold Book - auto-acceleration
DOI: 10.1351/goldbook.15380
Status: current

Definition
Increase in the rate of polymerization with increasing conversion of the reactant(s).

Example
In a polymerization, auto-acceleration may be due to a variety of causes. An example of auto-acceleration in a polymerization is the Norrish–Trommsdorf effect (gel effect) which leads to a significant increase in the rate of radical polymerization with monomer conversion. The effect is due to the rate of termination decreasing with increasing viscosity of the system, causing an increase in the concentration of propagating radicals.

Related Term
- rate of polymerization: https://goldbook.iupac.org//terms/view/15418

Source
- PAC, 2008, 80, 2163. 'Glossary of terms related to kinetics, thermodynamics, and mechanisms of polymerization (IUPAC Recommendations 2008)' on page 2166 (https://doi.org/10.1351/pac200880102163)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/15380/html
- json: https://goldbook.iupac.org/terms/view/15380/json
- xml: https://goldbook.iupac.org/terms/view/15380/xml

Citation: Citation: 'auto-acceleration' 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.15380
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Accessed: 2026-04-18T06:47:44+00:00