| Abstract
| - A simple ethylene polymerization system based on aluminum is reported, comprising a Lewis acidic aluminum alkyl reagent such as methylaluminum sesquichloride (Al2Cl3Me3), and a chlorine source, such as ethyl trichloroacetate or p-toluene sulfonyl chloride.
- Methylaluminum sesquichloride (Al2Cl3Me3, MAS), in the presence of ethyl trichloroacetate (ETAC),is found to be an effective catalyst for the production of polyethylene. Optimal catalyst productivities areobtained for a MAS:ETAC ratio of 1:1 at a reaction temperature of 75 °C. The polymerization is firstorder in both ethylene and MAS/ETAC concentration. NMR studies indicate that a 1:1 adduct is formedbetween binuclear MAS and ETAC, which is postulated to be a direct precursor to the active species.The productivity at elevated temperatures is limited by a radical decomposition process. Screening ofvarious additives revealed that many halogenated organic reagents can act as activators, including carbontetrachloride and p-toluene sulfonyl chloride. Improved productivities are obtained using sulfonyl chlorideactivators due to circumvention of radical decomposition pathways.
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