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Updated: Jul 5, 2026
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Ethylene Polymerizations Using Parallel Pressure Reactors and a Kinetic Analysis of Chain Transfer Polymerization
Published on: November 27, 2015
From unstable to stable: half-metallocene catalysts for olefin polymerization.
Prabhuodeyara M Gurubasavaraj1, Herbert W Roesky, Bijan Nekoueishahraki
1Institute of Inorganic Chemistry, University of Göttingen, Göttingen, Germany.
Inorganic Chemistry
|May 22, 2008
Summary
New organoaluminum compounds (2-4) were synthesized and found to be thermally stable. Half-metallocene complex 3 exhibited higher activity in ethylene polymerization than complex 2.
Area of Science:
- Organometallic Chemistry
- Polymerization Catalysis
Background:
- Precursors like CpTiMe3 and Cp*ZrMe3 are prone to decomposition below room temperature.
- There is a need for more stable catalysts in olefin polymerization.
Purpose of the Study:
- To synthesize novel organoaluminum-metal complexes.
- To investigate the thermal stability of these new compounds.
- To evaluate their catalytic activity in ethylene polymerization.
Main Methods:
- Reaction of LAlMeOH with various metal precursors (CpTiMe3, Cp*TiMe3, Cp*ZrMe3).
- Characterization using single-crystal X-ray structural analysis.
- Ethylene polymerization tests in the presence of methylaluminoxane.
Main Results:
- Synthesis of stable compounds LAlMe(mu-O)TiMe2Cp (2), LAlMe(mu-O)TiMe2Cp* (3), and LAlMe(mu-O)ZrMe2Cp* (4).
- Compounds 2-4 exhibit enhanced thermal stability compared to precursors.
- Half-metallocene complex 3 shows higher catalytic activity in ethylene polymerization than complex 2, with polydispersities between 2.8 and 4.2.
Conclusions:
- The synthesized organoaluminum-metal complexes offer improved thermal stability.
- Half-metallocene complex 3 is a promising catalyst for ethylene polymerization.
- No copolymerization with styrene was observed.
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