Gas phase polymerisation of ethylene

Patent metadata

Field	Value
Publication number	US-2019016831-A1
Application number	US-201716070536-A
Country	US
Kind code	A1
Filing date	Jan 19, 2017
Priority date	Jan 21, 2016
Publication date	Jan 17, 2019
Grant date	—

Abstract

The invention relates to a process for the production of polyethylene by gas phase polymerisation of ethylene in the presence of a supported chromium oxide based catalyst which is modified with an amino alcohol wherein the molar ratio of amino alcohol:chromium ranges between 0.5:1 and 1.5:1 wherein the support is silica having a surface area (SA) between 250 m2/g and 400 m2/g and a pore volume (PV) between 1.1 cm3/g and less than 2.0 cm3/g.

First claim

1 . A process for the production of polyethylene by gas phase polymerisation of ethylene in the presence of a supported chromium oxide based catalyst composition which is modified with an amino alcohol wherein the molar ratio of amino alcohol:chromium ranges between 0.5:1 and 1.5:1, wherein the support is silica having a surface area (SA) between ≥450 m 2 /g and ≤550 m 2 /g and a pore volume (PV) between ≥1.7 cm 3 /g and ≤2.0 cm 3 /g and wherein the catalyst comprises a titanium compound.

2 . The process according to claim 1 characterised in that the amount of chromium in the supported catalyst is ≥0.1% by weight and ≤0.5% by weight.

3 . The process according to claim 1 , characterised in that the molar ratio of amino alcohol:chromium ranges between 0.7:1 and 1.5:1.

4 . The process according to claim 1 , characterised in that the molar ratio of amino alcohol:chromium ranges between 1:1 and 1.3:1.

5 . The process according to claim 1 , characterised in that the amino alcohol has the formula

wherein
the R groups may be, independently of one other the same or different, a C 1 -C 10 alkyl group, and
R 1 is a C 3 -C 8 cycloalkyl group or a C 4 -C 16 alkyl substituted cycloalkyl group.

6 . The process according to claim 5 characterised in that the amino alcohol is 4-(cyclohexylamino) pentan-2-ol or 4-[(2-methylcyclohexyl) amino]pentan-2-ol.

7 . The process according to claim 1 , characterised in that the titanium compound a compound according to the formulas Ti (OR 1 ) n X 4-n and Ti (R 2 ) n X 4-n , wherein
R 1 and R 2 represent an (C 1 -C 20 ) alkyl group, (C 1 -C 20 ) aryl group or (C 1 -C 20 ) cycloalkyl group, X represents a halogen atom, and n represents a number satisfying 0≥n≤4.

8 . Polyethylene obtained with the process according to claim 1 , characterised in that the polyethylene has
a high-load melt index (HLMI)≥5 g/10 min and ≤10 g/10 min (according to ISO 1133); M w /M n ≥20 and ≤30 (according to size exclusion chromatography (SEC) measurement); and a density ≥945 kg/m 3 and ≤965 kg/m 3 (according to IS01183).

9 . An article prepared using the products obtained with the process according to claim 1 .

10 . Container, jerry can or intermediate bulk container prepared using the products obtained with the process according to claim 1 .

11 . The process according to claim 1 characterised in that
the amount of chromium in the supported catalyst is ≥0.1% by weight and ≤0.5% by weight,
the molar ratio of amino alcohol:chromium ranges between 1:1 and 1.3:1, and
the amino alcohol has the formula

wherein
the R groups may be, independently of one other the same or different, a C 1 -C 10 alkyl group, and
R 1 is a C 3 -C 8 cycloalkyl group or a C 4 -C 16 alkyl substituted cycloalkyl group.

12 . The process according to claim 11 characterised in that the titanium compound is a compound according to the formulas Ti (OR 1 ) n X 4-n and Ti (R 2 ) n X 4-n , wherein
R 1 and R 2 represent an (C 1 -C 20 ) alkyl group, (C 1 -C 20 ) aryl group or (C 1 -C 20 ) cycloalkyl group,
X represents a halogen atom, and
n represents a number satisfying 0≥n≤4.

Assignees

• Sabic Global Technologies Bv

Inventors

• Hamed Orass
• Aliyev Vugar
• Al-Sayari Omar

Classifications

• C08F2/34 Primary

  Polymerisation in gaseous state · CPC title

• C08F2500/12

  Melt flow index or melt flow ratio · CPC title

• C08F2500/18

  Bulk density · CPC title

• C08F4/69

  Chromium, molybdenum, tungsten or compounds thereof · CPC title

• C08F4/025

  Metal oxides · CPC title