| 摘要 |
<p>A catalytic component for polymerizing olefins comprises a solid support containing magnesium-halogen or manganese-halogen bonds, a transition metal halide of a metal selected from Groups IVB and VB of the periodic table, and electron donors. This catalytic component is obtainable by steps comprising: (a) contacting a mixture comprising a magnesium halide or manganese halide and at least one electron donor with a Ti(OR) 4 compound to form a solution, where R is a hydrocarbyl or halogenated hydrocarbyl moiety containing 1 to 20 carbon atoms or a halogen, and (b) reacting the solution with a reagent com prising a transition metal halide selected from Groups IVB and VB of the periodic table, whereby, with a suitable cocatalyst, polyolefin is formed with high activity, showing a high Isotactic Index, and with a narrow range of particle size distribution.</p> |
