PROCESS FOR THE PREPARATION OF TITANIUM TRICHLORIDE STARTING AT LOW TEMPERATURE AND ITS USE IN THE POLYMERIZATION OF ETHYLENICALLY UNSATURATED HYDROCARBONS

摘要

Titanium trichloride-containing compositions for use as catalyst component in stereoregular olefin polymerization are prepared by gradual addition of a solution of titanium tetrachloride to a solution of trialkyl aluminum in certain low-boiling inert diluents. The mixture is prepared and held at a temperature below about -90 DEG C until addition is complete, is thereafter gradually warmed up at least to ambient temperature but not above 80 DEG C and held until reduction of TiCl4 to TiCl5 is complete, and is then heated to an elevated temperature at which the TiCl3 is converted to the violet form. Refinements of this procedure include control of mixing and heating rates and post-treatment of the reaction product to produce catalyst components having various desired properties.