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Controlled Photoredox Ring-Opening Polymerization of O-Carboxyanhydrides Mediated by Ni/Zn Complexes
Published on: November 21, 2017
Kinetic subtleties of nitroxide mediated polymerization
Denis Bertin1, Didier Gigmes, Sylvain R A Marque
1Laboratoire Chimie Provence UMR 6264, Université d'Aix-Marseille I-III, case 521, Avenue Escadrille Normandie-Niemen, 13397 Marseille Cedex 20, France.
Chemical Society Reviews
|January 15, 2011
Summary
Nitroxide Mediated Polymerization (NMP) kinetics require a detailed 3-stage model, including initiation, propagation, and termination. Understanding alkoxyamine homolysis and radical addition is crucial for successful NMP.
Area of Science:
- Polymer Chemistry
- Chemical Kinetics
- Materials Science
Background:
- Nitroxide Mediated Polymerization (NMP) is of significant academic and industrial interest.
- Simplified kinetic models for NMP, while useful, are insufficient for describing all kinetic effects.
- NMP, like conventional radical polymerization, involves initiation, propagation, and termination stages.
Purpose of the Study:
- To provide a comprehensive review of the fundamental kinetics of Nitroxide Mediated Polymerization.
- To highlight the limitations of simplified kinetic schemes in NMP.
- To emphasize the importance of specific initiation steps in NMP.
Main Methods:
- Analysis of established kinetic schemes for radical polymerization.
- Discussion of activation/deactivation processes involving dormant species in NMP.
- Review of experimental evidence regarding NMP kinetics.
Main Results:
- NMP requires a more detailed kinetic description than previously thought, incorporating initiation, propagation, and termination.
- The activation/deactivation equilibrium between dormant and active species is central to NMP kinetics.
- The rate of alkoxyamine homolysis and initial alkyl radical addition significantly impacts NMP success.
Conclusions:
- A 3-stage kinetic model is necessary for accurately describing NMP.
- Understanding the kinetics of initiation, propagation, and termination, including side reactions, is vital for controlling NMP.
- Further investigation into the fundamental kinetics of NMP is warranted.
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