Multicentered self-immobilized ethylene polymerization catalysts based on functionalized titanium halide salicylaldiminate complexes for the synthesis of ultra-high-molecular-weight polyethylene

• Published in: Russian journal of applied chemistry 2012-09, Vol.85 (9), p.1404-1412
• Main Authors: Ivancheva, N. I., Khaikin, S. Ya, Sviridova, E. V., Fedorov, S. P., Sanieva, D. V., Molev, O. V., Oleinik, I. V., Ivanchev, S. S.
• Format: Article
• Language: English
• Subjects: Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Industrial Chemistry/Chemical Engineering; Macromolecular Compounds and Polymeric Materials
• ISSN: 1070-4272; 1608-3296
• DOI: 10.1134/S1070427212090170

Specific features of ethylene polymerization using a new group of catalytic systems based on ten methylalumoxane-activated titanium halide salicylaldiminato complexes functionalized with ω-vinylalkoxy groups and containing tert-butyl substituents in the phenoxide moiety were studied. The catalytic activity of the new group of activated complexes is strongly affected by the position of the ω-vinylalkoxy functional group and by the number and position of substituents in the phenoxide moiety. These factors determine the ratio of the homogeneous and heterogeneous steps of the polymerization as a result of the catalyst self-immobilization onto the polymer formed, and also the molecular characteristics of the polymer obtained at 20, 40, and 60°C and ethylene pressure of 0.4 MPa. The possibility and conditions of preparing ultra-high-molecular-weight polyethylene with improved morphology were revealed.