Homo- and Heteroligated Salicylaldiminato Titanium Complexes with Different Substituents Ortho to the Phenoxy Oxygens for Ethylene and Ethylene/1-Hexene (Co)polymerization

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• 作者：Erdong Yao ; Jianchun Wang ; Zhongtao Chen ; Yuguo Ma
• 刊名：Macromolecules
• 出版年：2014
• 出版时间：December 9, 2014
• 年：2014
• 卷：47
• 期：23
• 页码：8164-8170
• 全文大小：329K
• ISSN：1520-5835

文摘

A series of homoligated (1c鈥?b>1e) and heteroligated (2a鈥?b>2e) salicylaldiminato titanium dichloride complexes with different substituents ortho to the phenoxy oxygens were efficiently prepared. X-ray diffraction studies on these new dichloride complexes 2b, 2d, and 2e reveal a distorted octahedral coordination of the central metal. In the presence of dried methylaluminoxane, all the complexes exhibit high ethylene polymerization productivities. Surprisingly, complex 1d incorporating an o-(trimethylsilyl)ethynyl group displays the highest activity [5.26 脳 10³ kg of polyethylenes (mol Ti)^鈭? h^鈥?]. In ethylene/1-hexene copolymerization, the heteroligated complexes 2a鈥?b>2e display improved activities and intermediate incorporation ability compared with their homoligated counterparts 1a鈥?b>1f. The activity and incorporation ability for 1-hexene are highly dependent on the nature of the ortho-substituents. Among them, (trimethylsilyl)ethynyl-substituted precatalyst (1d) achieves the highest incorporation ratio (27.3 mol %), while ethynyl-substituted precatalyst (2c) achieves the highest copolymerization activity [2.89 脳 10³ kg of copolymers (mol Ti)^鈭? h^鈥?].