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Novel titanium(IV) complexes with 2,4ditertbutyl 6(1,1,1,3,3,3hexafluoro2hydroxypropan2yl)phenolin ethene polymerizationстатья
Информация о цитировании статьи получена из
Web of Science,
Scopus
Статья опубликована в журнале из списка Web of Science и/или Scopus
Дата последнего поиска статьи во внешних источниках: 18 июля 2013 г.
- Авторы: Solov´ev M.V., Gagieva S.Ch, Tuskaev V.A., Bravaya N.M., Gadalova O.E., Khrustalev V.N., Borissova A.O., Bulychev B.M.
- Журнал: Russian Chemical Bulletin
- Том: 60
- Номер: 11
- Год издания: 2011
- Издательство: Springer Nature
- Местоположение издательства: Switzerland
- Первая страница: 2227
- Последняя страница: 2235
- DOI: 10.1007/s11172-011-0342-1
- Аннотация: Dinuclear (2) and mononuclear dichloride complexes (3) of titanium(iv) isopropoxide with a bidentate phenol alcohol ligand, viz., 2,4-di-tert-butyl-6-(1,1,1,3,3,3-hexafluoro-2-hydroxy-propan-2-yl)phenol, were obtained. The structures of the complexes were confirmed by X-ray diffraction. The dimeric structure of complex 2 is typical of alkoxy compounds and contains the bridging fragment Ti(μ-OPri)2Ti; the coordination polyhedron of the Ti atom is a distorted tetragonal pyramid. In complex 3, the Ti atom has a distorted octahedral environment made up of the O atoms of the ligand, the Cl atoms, and the O atoms of two coordinated propan-2-ol molecules. The catalytic properties of complexes 2 and 3 in ethene polymerization were studied with such promoters as polymethylaluminoxane (MAO), trimethylaluminum, triisobutylaluminum, diethylaluminum chloride, and Et2AlCl-MgBu2. Both the complexes were catalytically active (635 and 540 kg of polyethylene (PE)/(mol of Ti) h atm, respectively) only in the presence of the binary promoter Et2AlCl-MgBu2. The dichloride complexes obtained from a lithium or magnesium salt of the same ligand and TiCl4 without separation from lithium and magnesium chlorides formed as by-products were catalytically active in the presence of MAO, Bui3Al, and Me3Al. For the catalytic system containing the dichloride complex and MgCl2, the best promoter is Me3Al (1082 kg of PE/(mol of Ti) h atm). The polymer obtained on all the catalytic systems is linear polyethylene characterized by high molecular weight (Mw = = 593900–2000000 g mol−1) and high polydispersity indices (Mw/Mn = 2.8–15). Various conjectures were made about why lithium and magnesium chlorides have the promoting effects.
- Добавил в систему: Гагиева Светлана Черменовна