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Kinetic regularities of catalytic ethylene polymerization on single- and multi-site cobalt and vanadium bis(imino)pyridine complexes

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Abstract

The number of active centers C p in the homogeneous complexes LCoCl2 and LVCl3 (L = 2,6-(2,6-R2C6H3N=CMe)2C5H3N; R = Me, Et, tBu) and the propagation rate constants k p have been determined by the radioactive 14CO quenching of ethylene polymerization on these complexes in the presence of the methylaluminoxane (MAO) activator. For the systems studied, a significant portion of the initial complex (up to 70%) transforms into polymerization-active centers. The catalysts based on the cobalt complexes are single-site, and the constant k p in these systems is independent of the volume of substituent R in the ligand, being (2.4−3.5) × 103 L mol−1 s−1 at 35°C. The much larger molecular weight of the polymer formed on the complex with the tert-butyl substituent in the aryl rings of the ligand compared to the product formed on the complex with the methyl substituent is due to the substantial (∼11-fold) decrease in the rate constant of chain transfer to the monomer. At the early stages of the reaction (before 5 min), the vanadium complexes contain active centers of one type only, for which k p = 2.6 × 103 L mol−1 s−1 at 35°C. An increase in the polymerization time to 20 min results in the appearance, in the vanadium systems, of new, substantially less reactive centers on which high-molecular-weight polyethylene forms. The number of active centers C p in the 2,5-tBu2LCoCl2 and 2,6-Et2LVCl3 systems with the MAO activator increases as the polymerization temperature is raised from 25 to 60°C. The activation energies of the chain propagation reaction (E p) have been calculated. The value of E p for complex 2,5-tBu2LCoCl2 is 4.5 kcal/mol. It is assumed that the so-called “dormant” centers form in ethylene polymerization on the 2,6-Et2LVCl3 complex, and their proportion increases with a decrease in the polymerization temperature. Probably, the anomalously high value E p = 14.2 kcal/mol for the vanadium system is explained by the formation of these “dormant” centers.

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References

  1. Britovsek, G.J., Gibson, V.C., Kimberley, B.S., Maddox, P.J., McTavish, S.J., Solan, G.A., White, A.J., and Williams, D.J., Chem. Commun., 1998, no. 7, p. 849.

    Google Scholar 

  2. Small, B.L., Brookhart, M., and Bennet, A.M., J. Am. Chem. Soc., 1998, vol. 120, no. 16, p. 4049.

    Article  CAS  Google Scholar 

  3. Reardon, D., Conan, F., Gambarotta, S., Yap, G., and Wang, Q.Y., J. Am. Chem. Soc., 1999, vol. 121, no. 40, p. 9318.

    Article  CAS  Google Scholar 

  4. Schmidt, R., Welch, M.B., Knudsen, R.D., Gottfried, S., and Alt, H.G., J. Mol. Catal. A: Chem., 2004, vol. 222, nos. 1–2, p. 9.

    CAS  Google Scholar 

  5. Britovsek, G.J., Bruse, M., Gibson, V.C., Kimberley, B.S., Maddox, P.J., Mastroianni, S., McTavish, S.J., Redshaw, C., Solan, G.A., Stromberg, S., White, A.J., and Williams, D.J., J. Am. Chem. Soc., 1999, vol. 121, no. 38, p. 8728.

    Article  CAS  Google Scholar 

  6. Soshnikov, I.E., Semikolenova, N.V., Bushmelev, A.N., Bryliakov, K.P., Lyakin, O.Y., Redshaw, C., Zakharov, V.A., and Talsi, E.P., Organometallics, 2009, vol. 28, no. 20, p. 6003.

    Article  CAS  Google Scholar 

  7. Kim, I., Han, B.H., Ha, Y.S., Ha, C.S., and Park, D.W., Catal. Today, 2004, vol. 93–95, p. 281.

    Article  Google Scholar 

  8. Kim, I., Han, B.H., Kim, J.S., and Ha, C.S., Macromol. Res., 2005, vol. 13, no. 1, p. 2.

    Article  CAS  Google Scholar 

  9. Liu, J.Y., Zheng, Y., Li, Y.G., Pan, L., Li, Y.S., and Hu, N.H., J. Organomet. Chem., 2005, vol. 690, no. 5, p. 1233.

    Article  CAS  Google Scholar 

  10. Schmidt, R., Welch, M.B., Knudsen, R.D., Gottfried, S., and Alt, H.G., J. Mol. Catal. A: Chem., 2004, vol. 222, nos. 1–2, p. 17.

    CAS  Google Scholar 

  11. Semikolenova, N.V., Zakharov, V.A., Echevskaja, L.G., Matsko, M.A., Bryliakov, K.P., and Talsi, E.P., Catal. Today, 2009, vol. 144, nos. 3–4, p. 334.

    Article  CAS  Google Scholar 

  12. Colamarco, E., Milione, S., Cuomo, C., and Grassi, A., Macromol. Rapid Commun., 2004, vol. 25, no. 2, p. 450.

    Article  CAS  Google Scholar 

  13. Semikolenova, N.V., Zakharov, V.A., Talsi, E.P., Babushkin, D.E., Sobolev, A.P., Echevskaya, L.G., and Khusniyarov, M.M., J. Mol. Catal. A: Chem., 2002, vols. 182–183, nos. 1–2, p. 283.

    Article  Google Scholar 

  14. Kooistra, T.M., Knijnenburg, Q., Smits, J.M.M., Horton, A.D., Budzelaar, P.H.M., and Gal, A.W., Angew. Chem. Int. Ed., 2001, vol. 40, no. 24, p. 4719.

    Article  CAS  Google Scholar 

  15. Barabanov, A.A., Bukatov, G.D., Zakharov, V.A., Semikolenova, N.V., Echevskaja, L.G., and Matsko, M.A., Macromol. Chem. Phys., 2005, vol. 206, no. 22, p. 2292.

    Article  CAS  Google Scholar 

  16. Barabanov, A.A., Bukatov, G.D., Zakharov, V.A., Semikolenova, N.V., Echevskaja, L.G., and Matsko, M.A., Macromol. Chem. Phys., 2008, vol. 209, no. 24, p. 2510.

    Article  CAS  Google Scholar 

  17. Wu, J., Pan, Q., and Rempel, G.L., J. Appl. Polym. Sci., 2005, vol. 96, no. 3, p. 645.

    Article  CAS  Google Scholar 

  18. Barabanov, A.A., Bukatov, G.D., and Zakharov, V.A., J. Polym. Sci., Part A: Polym. Chem., 2008, vol. 46, no. 19, p. 6621.

    Article  CAS  Google Scholar 

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Authors and Affiliations

  1. Boreskov Institute of Catalysis, Siberian Branch, Russian Academy of Sciences, Novosibirsk, 630090, Russia

    A. A. Barabanov, N. V. Semikolenova, M. A. Mats’ko & V. A. Zakharov

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  1. A. A. Barabanov
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  2. N. V. Semikolenova
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  3. M. A. Mats’ko
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  4. V. A. Zakharov
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Correspondence to A. A. Barabanov.

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Original Russian Text © A.A. Barabanov, N.V. Semikolenova, M.A. Mats’ko, V.A. Zakharov, 2013, published in Kinetika i Kataliz, 2013, Vol. 54, No. 4, pp. 500–506.

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Barabanov, A.A., Semikolenova, N.V., Mats’ko, M.A. et al. Kinetic regularities of catalytic ethylene polymerization on single- and multi-site cobalt and vanadium bis(imino)pyridine complexes. Kinet Catal 54, 475–480 (2013). https://doi.org/10.1134/S0023158413040022

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  • DOI: https://doi.org/10.1134/S0023158413040022

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