Ethylene gas phase polymerisation process

Patent metadata

Field	Value
Publication number	US-10577435-B2
Application number	US-201615754445-A
Country	US
Kind code	B2
Filing date	Jul 27, 2016
Priority date	Aug 26, 2015
Publication date	Mar 3, 2020
Grant date	Mar 3, 2020

Abstract

The invention relates to a gas phase polymerisation process for the production of ethylene polymers in the presence of a catalyst composition based on a chromium compound, a titanium compound and a silica support material. The silica support material has a surface area (SA) between 685 m 2 /g and 800 m 2 /g, a pore volume (PV) between 1.65 and 1.85 cm 3 /g and an average particle size in the range between 25 and 35 micrometres. The catalyst composition is injected by a dry catalyst feeder into the polymerization reactor.

First claim

The invention claimed is:

1. A gas phase polymerisation process for the production of ethylene polymers, comprising: polymerizing ethylene in the presence of a catalyst composition based on a chromium compound, a titanium compound and a silica support material characterized in that the silica support material has a surface area (SA) ≥685 m 2 /g and ≤800 m 2 /g, a pore volume (PV) ≥1.65 and ≤1.85 cm 3 /g and an average particle size in the range ≥25 and ≤35 micrometres, wherein the catalyst composition does not comprise a magnesium compound.

2. The process according to claim 1 , wherein the surface area (SA) ≥700 m 2 /g.

3. The process according to claim 1 , wherein the pore volume (PV) is ≥1.7 cm 2 /g.

4. The process according to claim 1 , wherein the average particle size is ≥33 micrometres.

5. The process according to claim 1 , wherein the catalyst composition is injected by a dry catalyst feeder into the polymerization reactor.

6. The process according to claim 1 , wherein the catalyst composition is a dry catalyst composition.

7. The process according to claim 1 , wherein the polymerization of ethylene takes place in a gas phase polymerization in the presence of a comonomer.

8. The process according to claim 7 , wherein the comonomer is 1-hexene.

9. The process according to claim 1 , wherein the ethylene polymer has high load melt index (HLMI) ≥2 g/10 min and ≤10 g/10 min (HLMI determined using the procedures of ASTM D-1238 Condition F using a load of 21.6 kg at a temperature of 190° C.)

10. The process according to claim 1 , wherein the ethylene polymer has
M w /M n between ≥8 and ≤15 (according to size exclusion chromatography (SEC) measurement),
density between ≥939 kg/m 3 and ≤955 kg/m 3 (according to ISO1183),
Izod impact strength (−30° C.) between ≥10 KJ/m 2 and ≤50 KJ/m 2 (according to ISO 180/A) and
resin bulk density between ≥450 kg/m 3 and ≤520 kg/m 3 (according to ASTM D-1895).

11. A gas phase polymerisation process for the production of ethylene polymers, comprising:
injecting a catalyst composition with a dry catalyst feeder into a gas phase polymerization reactor; and
polymerizing ethylene in the gas phase polymerization reactor in the presence of the catalyst composition;
wherein the catalyst composition is based on a chromium compound, a titanium compound, and a silica support material, wherein the silica support material has a surface area (SA) ≥685 m 2 /g and ≤800 m 2 /g, a pore volume (PV) ≥1.65 and ≤1.85 cm 3 /g and an average particle size in the range ≥25 and ≤35 micrometres; and
wherein the catalyst composition does not comprise a magnesium compound.

12. The process according to claim 11 , wherein the polymerizing is in the presence of 1-hexene.

13. The process according to claim 11 , wherein the ethylene polymer has
M w /M n between ≥8 and ≤15 (according to size exclusion chromatography (SEC) measurement);
density between ≥939 kg/m 3 and ≤955 kg/m 3 (according to ISO1183);
Izod impact strength (−30° C.) between ≥10 KJ/m 2 and ≤50 KJ/m 2 (according to ISO 180/A); and
resin bulk density between ≥450 kg/m 3 and ≤520 kg/m 3 (according to ASTM D-1895).

Assignees

• Sabic Global Technologies Bv

Inventors

• Hamed Orass M
• Al-Enazi Nayef M
• Aliyev Vugar O
• Meddad Abderrahman

Classifications

• B01J2523/00

  Constitutive chemical elements of heterogeneous catalysts · CPC title

• C08F2/34 Primary

  Polymerisation in gaseous state · CPC title

• B01J8/0015

  Feeding of the particles in the reactor; Evacuation of the particles out of the reactor · CPC title

• B01J21/063

  Titanium; Oxides or hydroxides thereof · CPC title

• B60K15/03

  Fuel tanks · CPC title