Catalyst for producing polyolefins

Abstract

A catalyst suitable for polymerizing an .alpha.-olefin, comprising a solid catalyst component [A] and an organometal compound [B], the solid catalyst component [A] being prepared by reacting an organomagnesium compound (1) soluble in a hydrocarbon medium and represented by the general formula, MgR.sub.p.sup.1 R.sub.q.sup.2 X.sub.r.Z.sub.s wherein R.sup.1 is a hydrocarbon group having 2 to 3 carbon atoms; R.sup.2 is a hydrocarbon group having 4 to 20 carbon atoms and the difference in number of carbon atoms between R.sup.1 and R.sup.2 is at least 2; X is an electronegative group having an oxygen atom, a nitrogen atom or a sulfur atom; Z is an organometal compound of aluminum, boron, beryllium, zinc, silicon or lithium; p and q each is a number above 0 to 1; r is a number from 0 to 1; p+q+r=2; and s is a number from 0.02 to 0.09, with a titanium and/or vanadium compound (2) having at least one halogen atom; and a process for polymerizing an .alpha.-olefin employing the same catalyst.

Dependencies are inferred from the claim text.