Method for preparing transition metal component of Ziegler-Natta catalysts

摘要

A method for preparing Ziegler catalysts is disclosed wherein a mixture (A) containing the product resulting from mixing in an inert hydrocarbon diluent (1) a hydrocarbon soluble magnesium alkyl compound in said hydrocarbon solvent, (2) an aliphatic alcohol or carbon dioxide and (3) a titanium compound is reacted with (B) a reducing halide source in said hydrocarbon solvent. Components (A) and (B) are mixed at a constant initial temperature. When the magnesium concentration in component (A) and the metal concentration in component (B) are relatively low, the resultant polymer has a relatively narrow particle size distribution whereas when said concentration is relatively high, the resultant polymer has a relatively broad particle size distribution. When the ratio of the number of moles of aliphatic alcohol:total number of hydrocarbyl groups attached to the metal atom in component (1) is relatively low, the resultant polymer has a relatively small average particle size. When the ratio of the number of moles of aliphatic alcohol:total number of hydrocarbyl groups attached to the metal atom in component (1) is relatively high, the resultant polymer has a relatively large average particle size.