Abstract
A series of xanthene-bridged dinucleating ligands bearing imino- and aminopyridyl moieties and their nickel complexes were synthesized and characterized. The properties of these dinuclear complexes in ethylene polymerization were studied in comparison with the corresponding mononuclear nickel complexes. The iminopyridyl dinuclear nickel complexes activated by methylaluminoxane (MAO) showed higher catalytic activities (up to 2.2 × 106 g of PE (mol Ni)−1 h–1), higher molecular weights, and produced polyethylene with much lower branching density (27/1000C) than their mononuclear analogues. Similar trends were observed for the aminopyridyl dinuclear complexes. A metal–metal cooperativity effect was proposed to be able to slow down the β-hydride elimination and the corresponding chain-walking process. These results clearly demonstrated the great potentials of dinuclear nickel catalysts with the xanthene-bridged coordination modes in controlling the ethylene polymerization process as well as the microstructures...
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
