| 摘要 |
A catalyst composition for polymerizing alpha-olefins is prepared by treating a carrier with a mixture of at least one organomagnesium composition of the formula (OR')nMg(OR)m(I) where R and R' are the same or different C1-C12 hydrocarbyl groups, m and n are each 0, 1 or 2, m+n=valence of Mg, and a compound of the formula MXp(II) where M is Si, C, Ge or Sn, X is Cl or Br, and p is the valence of M, in a solvent capable of dissolving the mixture. The product of this step may or may not be dried. Subsequently, it is contacted with a transition metal compound. The polymer resins produced with the resulting catalyst have relatively narrow molecular weight distribution and high melt index values.
|
