Abstract:
A method for increasing the solubility of a magnesium halide includes providing an electron donating solvent, contacting a magnesium halide with the solvent; and providing an electron donor compound to form a magnesium halide composition. The composition is characterized by solubility in the electron donor solvent that does not decrease up to the boiling point of the solvent. A polymerization catalyst precursor composition comprises the product of mixing the magnesium halide composition with a transition metal compound. Active catalysts prepared from such precursors and a method of polymerization using such catalysts are also disclosed.