Catalysts Based on Magnesium Diethoxide and TiCl

Bohm s data obtained from electron microscopy also showed that the original catalyst particles were completely disintegrated during the polymerization process, as no catalyst residues were detected in the polymer. Hence, catalyst residue must be smaller than -50 A. 

Additional data reported by Bohm showed that the interaction of the triethylalmninum cocatalyst with the solid catalyst precursor took place in less than 5 minutes and that catalyst activity was a function of the Al/ Ti molar ratio, with higher activity at an Al/Ti ratio of about 8-30. Longer reduction times of up to four hours did not affect catalyst activity. 

Two important conclusions from this investigation were (1) catalyst systems prepared by reducing TiCl with organomagnesium compoimds are much more active (factor of 3-10) than catalysts prepared by reducing TiCl with aluminum alkyls, and (2) organomagnesium compoimds reduced the titanium center to up to 41% Ti(II) and the catalyst systems still maintained a very high activity. 

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