| 摘要 |
<p>A process for polymerizing one or more α-olefins of up to 10 carbon atoms which comprises contacting the one or more α-olefin under polymerization conditions with a catalyst system comprising: (a) a titanium halide-containing magnesium, titanium, halide and polycarboxylic acid containing a pro-catalyst component wherein the component is obtained by contacting a magnesium compound of the formula MgR'R', wherein R' and R' are, independently, alkoxide group, aryloxide group or halogen, with a halogenated tetravalent titanium compound in the presence of a halohydrocarbon and a polycarboxylic acid ester electron donor, (b) an organo-aluminum cocatalyst component, and (c) an organosilane selectivity control agent represented by general formula (I), wherein R?1 and R2¿ are, independently, alkyl groups containing from 1 to 12 carbon atoms; aryl groups containing from 1 to 12 carbon atoms, alkaryl groups containing from 1 to 12 carbon atoms, aralkyl groups containing from 1 to 12 carbon atoms, hydrocarbyloxy groups containing 1 to 12 carbon atoms or halogen; and R?3 and R4¿ are hydrocarbyloxy groups containing from 2 to 12 carbon atoms. The process affords high catalyst productivity and produces polymer products having improved polymer properties such as broad molecular weight distribution, and high stiffness while retaining low oligomer content.</p> |
