US 5,753,578 A · Metallocene catalyst for the (CO)polymerization of .alpha.-olefins

Abstract

A catalyst active in the (co)polymerization of .alpha.-olefins is obtained by putting the following components in contact with each other: (i) a "bridged" bis-metallocene derivative of a metal M selected from titanium, zirconium or hafnium, wherein the divalent "bridge" has a rigid structure linked to two .eta..sup.5 -cyclopentadienyl ring with two methylene groups having a distance from each other of less than 3.5 .ANG.; (ii) a co-catalyst consisting of an organic derivative of a metal M' selected from boron, aluminium, gallium and tin. Such a catalyst allows high polymerization rates to be reached and is particularly suitable for high temperature polymerization process and co-polymerization of ethylene with other .alpha.-olefins.

Claims29

Dependent claims

A catalyst for the (co)polymerization of ethylene and/or .alpha.-olefins comprising the following two components put in contact with each other:

(i) a metallocene complex having the following general formula (I):
##STR14## wherein:
M represents a metal selected from the group consisting of titanium, zirconium and hafnium,
A' and A" each independently represent an organic group containing a .eta..sup.5 -cyclopentadienyl anion co-ordinated to the metal M,
R' and R" each independently represent an anionic group linked to the metal M;
B represents a divalent organic group comprising an unsaturated group linked to two --CH.sub.2 --methylene groups so that they form with this unsaturated group a rigid molecular structure, and the distance between the two --CH.sub.2 methylene groups in the space is less than 3.5 .ANG.;
(ii) a co-catalyst consisting of an organic compound of a metal M' selected from the group consisting of boron, aluminum, gallium and tin;
with the proviso that, when the groups A' and A" are both .eta..sup.5 -indenyl (C.sub.9 H.sub.7), the divalent organic group B is different from ortho-phenylene.

5 more elements

A process for the preparation of a co-polymer of ethylene and at least one .alpha.-olefin having at least 3carbon atoms, comprising co-polymerizing ethylene and said .alpha.-olefin in suspension, solution or gas-phase, at a temperature from 0.degree. to 250.degree. C., and at a pressure of from 1 to 1200 atms in the presence of a catalyst including the following two components put in contact with each other:

(i) a metallocene complex having the following general formula (I):
##STR15## wherein:
M represents a metal selected from the group consisting of titanium, zirconium and hafnium,
A' and A" each independently represent an organic group containing a .eta..sup.5 -cyclopentadienyl anion co-ordinated to the metal M,
R' and R" each independently represent an anionic group linked to the metal M;
B represents a divalent organic group comprising an unsaturated group linked to two --CH.sub.2 -- methylene groups so that they form with this unsaturated group a rigid molecular structure, and the distance between the two --CH.sub.2 methylene groups in the space is less than 3.5 .ANG.;
(ii) a co-catalyst consisting of an organic compound of a metal M' selected from the group consisting of boron, aluminum, gallium and tin.

4 more elements

Dependencies are inferred from the claim text.

Metallocene catalyst for the (CO)polymerization of .alpha.-olefins

Life of this patent

Metallocene catalyst for the (CO)polymerization of .alpha.-olefins

Life of this patent

Abstract

Claims29