Peculiarities of Ethylene Polymerization Reactions with Bis(imino)pyridyl Complexes of CoCl2 and FeCl2

• Published in: Chinese journal of polymer science Vol. 42; no. 4; pp. 492 - 500
• Main Authors: Rishina, Laura A., Kissin, Yury V., Lalayan, Svetlana S., Antonov, Artem A., Krasheninnikov, Vadim G., Gulin, Alexander A.
• Format: Journal Article
• Language: English
• Published: Singapore Springer Nature Singapore 01-04-2024; Springer Nature B.V
• Subjects: Aluminum; Catalysts; Characterization and Evaluation of Materials; Chemistry; Chemistry and Materials Science; Condensed Matter Physics; Ethylene; Industrial Chemistry/Chemical Engineering; Iron chlorides; Low molecular weights; Magnesium; Molecular weight distribution; Polyethylenes; Polymer Sciences; Polymerization; Research Article; Transition metals; Polymer chain structure; Ethylene polymerization; and FeCl; Bis(imino)pyridyl complexes of CoCl; Molecular-weight distribution
• ISSN: 0256-7679; 1439-6203
• DOI: 10.1007/s10118-024-3064-1

The article describes ethylene polymerization reactions with transition metal catalysts based on complexes of CoCl
2
and FeCl
2
with an
N,N,N
-tridentate ligand 2,6-bis[1-(2,6-dimethylphenylimino)ethyl]pyridine. The complexes are converted into polymerization catalysts by reacting them either with polymethylalumoxane (MAO) or with a combination of Al(C
2
H
5
)
2
Cl and Mg(C
4
H
9
)
2
at an [Al]:[Mg] ratio of ~3. Both MAO-activated complexes readily polymerize ethylene at 35 °C with the formation of linear, low molecular weight polymers with a narrow molecular weight distribution. The same complexes, when activated with the Al(C
2
H
5
)
2
Cl-Mg(C
4
H
9
)
2
combination, form multi-center catalysts and generate polyethylenes with a broad molecular weight distribution.