Multi-metallic ziegler-natta procatalysts and cataysts prepared therefrom for olefin polymerizations

Patent metadata

Field	Value
Publication number	US-9255160-B2
Application number	US-201214116070-A
Country	US
Kind code	B2
Filing date	May 23, 2012
Priority date	Jun 1, 2011
Publication date	Feb 9, 2016
Grant date	Feb 9, 2016

Abstract

Novel catalyst compositions comprising three or more transition metals are effective in increasing catalyst efficiency, reducing polydispersity, and increasing uniformity in molecular weight distribution when used in olefin, and particularly, linear low density polyethylene (LLDPE), polymerizations. The resulting polymers may be used to form differentiated products including, for example, films that may exhibit improved optical and mechanical properties.

First claim

What is claimed is:

1. A process to prepare a multi-metallic procatalyst comprising
(a) reacting a hydrocarbon-soluble organomagnesium compound or complex thereof and an active non-metallic or metallic halide to form a halogenated magnesium support;
(b) contacting the magnesium halide support with a conditioning compound containing an element selected from the group consisting of boron, aluminum, gallium, indium and tellurium under conditions sufficient to form a conditioned magnesium halide support;
(c) contacting the conditioned magnesium halide support and a compound containing, as a first metal, titanium, to form a supported titanium compound;
(d) contacting the supported titanium compound and a second metal and a third metal independently selected from the group consisting of zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, and tungsten, provided that the second metal and the third metal are not the same; and further provided that the molar ratio of the magnesium to a combination of the titanium and the second and third metals ranges from 30:1 to 5:1; under conditions sufficient to form a multi-metallic procatalyst.

2. A multi-metallic procatalyst obtained according to the process of claim 1 .

3. The procatalyst of claim 2 wherein the molar ratio of magnesium to titanium ranges from 8:1 to 80:1.

4. A multi-metallic polymerization catalyst comprising the reaction product of the multi-metallic procatalyst of claim 2 and an organometallic cocatalyst.

5. A polyethylene polymer prepared by a process wherein ethylene and optionally one or more olefin comonomers are polymerized in the presence of the multi-metallic polymerization catalyst of claim 4 .

6. The polyethylene polymer of claim 5 having a polydispersity (PDI) of less than 3.5, and a MWCCR in the range of 0.75 to 1.10.

7. The polyethylene polymer of claim 5 or 6 characterized as greater than or equal to 1 parts by combined weight of at least three metal residues remaining from the multi-metallic polymerization catalyst per one million parts of polyethylene polymer, where such metals are selected from the group consisting of titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, and combinations thereof, and wherein each said residual metal is present at least 0.4 ppm.

8. The polyethylene polymer of claim 5 or 6 , wherein said polyethylene is characterized by one of the following properties:
(a) a density in the range of from 0.900 to 0.960 g/cm 3 ; or
(b) a melt index (I 2 ) in the range of from 0.1 to 50 g/10 minutes; or
(c) a melt flow ratio (I 10 /I 2 ) in the range of from 6 to 10.

9. A composition comprising the polyethylene polymer of claim 5 or 6 , and one or more polymers or one or more additives.

10. An article comprising the polyethylene polymer of claim 5 or 6 .

Assignees

• Desjardins Sylvie
• Demirors Mehmet
• Donkers Ellen
• Fontaine Philip P
• Serrat Cristina
• Dow Global Technologies Llc

Inventors

• Desjardins Sylvie
• Demirors Mehmet
• Donkers Ellen
• Fontaine Philip P
• Serrat Cristina

Classifications

• C08F210/16

  Copolymers of ethene with alpha-alkenes, e.g. EP rubbers · CPC title

• C08J2323/06

  Polyethene · CPC title

• C08F10/02 Primary

  Ethene · CPC title

• D01F6/04

  from polyolefins · CPC title

• C08F2410/03

  Multinuclear procatalyst, i.e. containing two or more metals, being different or not · CPC title