Chapter 14. Mechanism and Kinetics of the Induction Period in Nitroxide Mediated Thermal Autopolymerizations. Application to the Spontaneous Copolymerization of Styrene and Maleic Anhydride

  1. Prof. Dr. Michael Buback4 and
  2. A. M. van Herk5
  1. José Bonilla-Cruz1,
  2. Laura Caballero2,
  3. Martha Albores-Velasco2,
  4. Enrique Saldívar-Guerra1,
  5. Judith Percino3 and
  6. Víctor Chapela3

Published Online: 31 MAY 2007

DOI: 10.1002/9783527610860.ch14

Radical Polymerization: Kinetics and Mechanism, Volume 248

Radical Polymerization: Kinetics and Mechanism, Volume 248

How to Cite

Bonilla-Cruz, J., Caballero, L., Albores-Velasco, M., Saldívar-Guerra, E., Percino, J. and Chapela, V. (2007) Mechanism and Kinetics of the Induction Period in Nitroxide Mediated Thermal Autopolymerizations. Application to the Spontaneous Copolymerization of Styrene and Maleic Anhydride, in Radical Polymerization: Kinetics and Mechanism, Volume 248 (eds M. Buback and A. M. van Herk), Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim, Germany. doi: 10.1002/9783527610860.ch14

Editor Information

  1. 4

    Institute of Physical Chemistry, Georg-August-University Göttingen, Tammannstrasse 6, D-37077 Göttingen, Germany

  2. 5

    Laboratory for Polymer Chemistry, Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, PO Box 513, 5600 MB Eindhoven, The Netherlands

Author Information

  1. 1

    Centro de Investigación en Química Aplicada, Blvd. Enrique Reyna 140, 25100, Saltillo, Coahuila México

  2. 2

    Facultad de Química, Universidad Nacional Autónoma de México, Coyoacán CU, México

  3. 3

    Laboratorio de Polímeros, Benemérita Universidad Autónoma de Puebla, Puebla, México

Publication History

  1. Published Online: 31 MAY 2007
  2. Published Print: 13 APR 2007

ISBN Information

Print ISBN: 9783527320561

Online ISBN: 9783527610860

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Keywords:

  • radical polymerization;
  • kinetics;
  • mechanism;
  • nitroxide mediated;
  • induction period;
  • autopolymerization;
  • styrene–maleic anhydride copolymerization;
  • Diels-Alder cycloaddition;
  • hydrogen abstraction

Summary

Recently we reported an experimental and theoretical (simulation) investigation on the mechanism of the induction period and the initial polymerization stages in the nitroxide mediated autopolymerization of styrene. In this paper we extend some of the results presented there and perform preliminary induction period experiments for the study of the mechanism and kinetics of the spontaneous copolymerization of styrene (S) and maleic anhydride (MA) in the presence of TEMPO and 4-OH-TEMPO. With even small amounts of MA (2% wt) the induction period is dramatically reduced by a factor of about 20 in comparison with the nitroxidemediated styrene autopolymerization at 120 °C. Our results suggest that the initiation mechanism involves a first step of reaction between S and MA. We speculate that this reaction is a Diels-Alder cycloaddition followed by hydrogen abstraction through a monomer or TEMPO assisted homolysis to form a radical pair (monomer case) or a single radical (TEMPO case), which either initiates polymerization or is trapped by TEMPO depending on the conditions. Hall and Padias have studied similar electron donor-acceptor co-monomer pairs and favor the formation of a tetramethylene diradical as the initiating species for spontaneous copolymerization. In any case, the rate-limiting step would be the initial reaction of S and MA. These induction experiments allow us to obtain an initial estimate of the order of magnitude for the kinetic constant of the rate-limiting step, as 10−6 Lmol−1s−1.