open access

https://hdl.handle.net/2115/90136

Exploring the Reaction Mechanism of Heterobimetallic Nickel-Alkali Catalysts for Ethylene Polymerization : Secondary-Metal-Ligand Cooperative Catalysis

英語

Mechanism

2022-07-07

Wiley-Blackwell

ChemCatChem

14(13)

e202200028

In this work, we explored the reaction mechanism of heterobimetallic nickel phenoxyphosphine polyethylene glycol (Ni-PEG) with alkali metals (M+=Li+, Na+, K+, and Cs+) catalysts for ethylene polymerization using the DFT calculations. The activation energy of the necessary step shows the following trend, Li+<Na+<K+<Cs+, which corresponds to experimentally observed activities. Roles of secondary metals (M+) in Ni-PEG catalysts were clarified. Our findings suggest that the active catalyst should contain strong cooperative metal-metal/metal-ligand interactions and less positive charge on M+ cation. Besides, the key role of M+ is to control the PEG group which stabilizes the catalyst structure. In addition, we found two key factors (shorter M-O-1 and M-O-PEG distances) for designing new catalysts from the pre-reaction state of the Ni-PEG(M+) catalysts. Finally, Ni-PEG(M2+) catalysts with Be2+, Mg2+, Co2+, and Zn2+ were suggested for candidates of highly active catalysts for ethylene polymerization.

学術雑誌論文

Accepted Manuscript

This is the peer reviewed version of the following article: P. Apilardmongkol, M. Ratanasak, J.-y. Hasegawa, V. Parasuk, ChemCatChem 2022, 14, e202200028., which has been published in final form at https://doi.org/10.1002/cctc.202200028. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions. This article may not be enhanced, enriched or otherwise transformed into a derivative work, without express permission from Wiley or by statutory rights under applicable legislation. Copyright notices must not be removed, obscured or modified. The article must be linked to Wiley’s version of record on Wiley Online Library and any embedding, framing or otherwise making available the article or pages thereof by third parties from platforms, services and websites other than Wiley Online Library must be prohibited.

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