Complexation of Cp2MCl2 in a Chloroaluminate Molten Salt: Relevance to Homogeneous Ziegler-Natta Catalysis
Abstract
Ethylene polymerization via Ziegler-Natta catalysis occurs in the ambient-temperature molten slat AlCl3-MEIC employing Cp2TiCl2 as the catalyst occurs only in melts with AlCl3:MEIC molar ratios. Cp2ZrCl2 and Cp2HfCl2 with AlCl3-XrX cocatalysts are not catalytically active in acidic melts. 1H NMR studies indicate formation of a strong 1:1 complex between Cp2TiCl2 and AlCl3, while Zr and Hf form much weaker 1:1 complexes due to strong Zr - Cl and Hf - Cl bonding. This stronger M - Cl bonding for Zr and Hf is proposed to preclude the initiation reaction for ethylene polymerization n the molten salt.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1990
- Accession Number
- ADA235846
Entities
People
- John S. Wilkes
- Richard T. Carlin
Organizations
- Air Force Research Laboratory