AbstractSome characteristics of alkoxylated catalysts derived from VOCl3and trialkylaluminum compounds have been examined for ethylene polymerization. Specifically studied were catalysts resulting from reaction of VOCl3with either an alcohol or an alkylaluminum alkoxide, or both, prior to reduction with a trialkylaluminum compound (R3Al). Although the two methods of preparing alkoxylated catalysts did not give identical results, certain overall generalizations can be drawn. In general, as the alkoxide content was increased, the molecular weight distribution was narrowed (by a simultaneous increase inM̄nand decrease inM̄w), polymerization rate was decreased, and the polymer melt index increased at a constant hydrogen level. Alkoxides had a negative effect on rate which could largely be overcome by raising the R3Al/V ratio or using continuous addition of R3Al. By suitably adjusting the alkoxide and hydrogen amounts, the complete range of molecular weights and molecular weight distribution of current commercial HDPE products can be mad