| abstract |
A process for producing alpha -olefin polymers with a controlled stereoregularity and with a higher yield is provided, which process comprises: combining a TiCl3-containing composition obtained by reducing TiCl4, with an organoaluminum compound; thereafter subjecting the composition to a polymerization treatment with an alpha -olefin; before, during or after the polymerization treatment, adding an electron donor or/and an electron acceptor or a reaction product of these two; as well as adding a reaction product of a trialkylaluminum with an electron donor having a specified molar ratio of the electron donor to the trialkylaluminum selected in the range of 0.01 to 5; and polymerizing an alpha -olefin in the presence of the resulting preactivated catalyst. |