Stereospecific bulk polymerization of propylene over ansa-zirconocene catalysts

P. M. Nedorezova; V. I. Tsvetkova; A. M. Aladyshew; D. V. Savinov; I. L. Dubnikova; V. A. Optov; D. A. Lemenovskii

doi:10.14314/polimery.2000.333

Published : 2022-09-21

Vol. 45 No. 5 (2000)

Stereospecific bulk polymerization of propylene over ansa-zirconocene catalysts

P. M. Nedorezova V. I. Tsvetkova A. M. Aladyshew D. V. Savinov I. L. Dubnikova V. A. Optov D. A. Lemenovskii

DOI: https://doi.org/10.14314/polimery.2000.333

Abstract

Bulk polymerization of propylene was studied over four ansa-zirconocene catalysts, viz., Me2SiInd2ZrCl2 (1), Me2Si(4-Ph-2-Et-Ind)2ZrCl2 (2) (rac:meso = 1:2), Ph2C(CpFlu)ZrCl2 (3), and Me2C(3-Me-CpFlu)ZrCl2 (4), which were characterized by different symmetries (C1, C2, Cs). The structure of the metallocene affected the structure of PP. Upon reactions with methylaluminoxane (MAO) or triisobutylaluminum (TIBA), compounds 1–4 pro-duced very active catalytic systems which catalyzed the polymerization to yield various structures of PP. Catalysts 1 and 2 gave isotactic PP, catalyst 3 gave syndiotactic PP and catalyst 4 gave hemiisotactic PP. Hemiiso-PP was similar in structure to amorphous PP and had no melting point. The catalytic activity of the system and molecular weight and stereospecificity of PP were studied in relation to the mode of preparation of the catalyst. Kinetic parameteres were evaluated, viz., time of insertion of the propylene molecule (0.001–0.0001 s) and the time of growth of a single PP macromo-lecule (3–6 s), and from these data the minimum degree of polymerization was determined. Activation energies were evaluated for the polymerization carried out over each catalyst system. Young's modulus, molecular weight and stereoregularity of the PP prepared were determined.

Keywords

propylen ; polimeryzacja ; ansa-cyrkonoceny ; izotaktyczny ; syndiotaktyczny i hemiizotaktyczny polipropylen ; ciężar cząsteczkowy PP ; aktywność katalityczna propylene ; polymerization ; ansa-zirconocenes ; isotactic ; syndiotactic and hemiisotactic PP ; molecular weight ; stereoregulatiry

Similar Articles

B. Świerz-Motysia, K. Pielichowski, Kinetics of decomposition of poly(vinyl chloride)/low-migration polyesterurethane plasticizer blend - a thermogravimetric study , Polimery: Vol. 50 No. 7-8 (2005)
E. Schab-Balcerzak, M.-A. Kakimoto, Curing of epoxy resin with hyperbranched polyamide , Polimery: Vol. 50 No. 4 (2005)
K. Kelar, K. Mencel, T. Sterzyński, M. Dutkiewicz, H. Maciejewski, Polyamide 6 modified with silsesquioxane prepared via anionic polymerization of e-caprolactam , Polimery: Vol. 57 No. 10 (2012)
I. Kaya, S. Çulhaoglu, Syntheses, structures and properties of novel oligo(azomethine ether)s containing or not chlorine atoms in the main chain , Polimery: Vol. 54 No. 4 (2009)
P. Król, B. Król, P. Chmielarz, J. Wojturska, Assessment of susceptibility to hydrolytic degradation of different types of polyurethanes in terms of their use as biomaterials , Polimery: Vol. 58 No. 4 (2013)
Z. Majchrzak, J. Lipczyński, Preparation and characteristics of polypropylene composites , Polimery: Vol. 52 No. 3 (2007)
J. Kucińska-Lipka, H. Janik, A. Balas, Syntheses, structures and chemical properties of unsaturated oligo(alkylene-ester-ether)diols , Polimery: Vol. 54 No. 7-8 (2009)
P. Zdebiak, P. El Fray, Influence of soft segments on thermal and mechanical properties of terpoly(ester-ether-ester)s , Polimery: Vol. 53 No. 10 (2008)
K. Gadzinowska, E. Piorkowska, Spherulite nucleation density from thin sections of bulk samples , Polimery: Vol. 49 No. 10 (2004)
J. Jęczalik, M. Baumann, Syntheses and photocuring of methacrylurethanes from polybutadienols differing in molecular weights , Polimery: Vol. 55 No. 2 (2010)

<< < 6 7 8 9 10 11 12 13 14 15 > >>

You may also start an advanced similarity search for this article.

Details

Statistics

Authors

Download files

PDF

Zasady cytowania

Nedorezova, P. M., Tsvetkova, V. I., Aladyshew, A. M., Savinov, D. V., Dubnikova, I. L., Optov, V. A., & Lemenovskii, D. A. (2022). Stereospecific bulk polymerization of propylene over ansa-zirconocene catalysts. Polimery, 45(5), 333–338. https://doi.org/10.14314/polimery.2000.333

P. M. Nedorezova polimery@ichp.pl

V. I. Tsvetkova

A. M. Aladyshew

D. V. Savinov

I. L. Dubnikova

V. A. Optov

D. A. Lemenovskii