Silica Supports With High Aluminoxane Loading Capability

Patent metadata

Field	Value
Publication number	US-2016355618-A1
Application number	US-201615142961-A
Country	US
Kind code	A1
Filing date	Apr 29, 2016
Priority date	Jun 5, 2015
Publication date	Dec 8, 2016
Grant date	—

Abstract

Olefin polymerization catalyst systems having high aluminoxane loading and methods for making and using them are disclosed herein.

First claim

What is claimed is:

1 . An olefin polymerization catalyst system comprising a silica support, wherein the silica support comprises silica gel particles having:
a. an average surface area of from about 400 to 800 m 2 /g; b. an average pore diameter of from about 60 to 200 Angstrom; and c. at least 20% of the incremental pore volume comprised of pores having a pore diameter larger than about 100 Angstrom; wherein the catalyst system further comprises an aluminoxane, and the aluminoxane loading on the support is greater than about 9.5 mmol Al/g silica.

2 . The catalyst system of claim 1 , wherein said silica gel particles have an average surface area of from about 550 to 650 m 2 /g.

3 . The catalyst system of claim 1 , wherein said silica gel particles have an average pore diameter of from about 80 to 130 Angstrom.

4 . The catalyst system of claim 1 , wherein said silica gel particles have an average pore volume of from about 0.5 to 2.5 ml/g of silica.

5 . The catalyst system of claim 1 , wherein said silica gel particles have an average particle size of from about 20 to 200 micrometers.

6 . The catalyst system of claim 1 , wherein at least 50% of the incremental pore volume is comprised of pores having a pore diameter larger than about 100 Angstrom.

7 . The catalyst system of claim 1 , wherein said aluminoxane is methylaluminoxane.

8 . The catalyst system of claim 1 , wherein said aluminoxane loading on the support is greater than about 12 mmol Al/g silica.

9 . The catalyst system of claim 1 , further comprising a single site catalyst component.

10 . The catalyst system of claim 1 , further comprising a metallocene catalyst component.

11 . The catalyst system of claim 1 , wherein a raw silica surface area and a supported aluminoxane surface area differ by about or less than 10%.

12 . The catalyst system of claim 1 , wherein a raw silica particle size and a supported aluminoxane particle size differ by about or less than 10% on a volumetric basis.

13 . The catalyst system of claim 1 , wherein the silica particles do not comprise agglomerates.

14 . A method for making an olefin polymerization catalyst system comprising contacting:
d. a silica support, wherein the silica support comprises silica gel particles having:
i. an average surface area of from about 400 to 800 m 2 /g;
ii. an average pore diameter of from about 60 to 200 Angstrom; and
iii. at least 20% of the incremental pore volume is comprised of pores having a pore diameter larger than about 100 Angstrom;
e. an aluminoxane; and f. an olefin catalyst component, wherein the catalyst system has an aluminoxane loading on the support of greater than about 9.5 mmol Al/g silica.

15 . The method of claim 14 , wherein said silica gel particles have an average surface area of from about 500 to 700 m 2 /g.

16 . The method of claim 14 , wherein said silica gel particles have an average pore volume of from about 0.5 to 2.5 ml/g of silica.

17 . The method of claim 14 , wherein said silica gel particles have an average particle size of from about 20 to 200 micrometers.

18 . The method of claim 14 , wherein at least 50% of the incremental pore volume is comprised of pores having a pore diameter larger than about 100 Angstrom.

19 . The method of claim 14 , wherein said aluminoxane is methylaluminoxane.

20 . The method of claim 14 , wherein said aluminoxane loading is greater than about 12 mmol Al/g silica.

21 . The method of claim 14 , wherein said olefin catalyst component is a single site catalyst component.

22 . The method of claim 14 , wherein said olefin catalyst component is a metallocene catalyst component.

23 . The method of claim 14 , wherein a raw silica surface area and a supported aluminoxane surface area differ by about or less than 10%, and/or wherein a raw silica particle size and a supported aluminoxane particle size differ by about or less than 10% on a volumetric basis.

24 . The method of claim 14 , wherein the silica particles do not comprise agglomerates.

25 . A method for polymerizing olefins using the catalyst system of claim 1 .

Assignees

• Exxonmobil Chemical Patents Inc

Inventors

• Luo Lubin
• Jain Anupriya
• Ye Xuan

Classifications

• C01P2006/12

  Surface area · CPC title

• C01P2006/16

  Pore diameter · CPC title

• C08F110/06 Primary

  Propene · CPC title

• C08F4/02

  Carriers therefor · CPC title

• C08F4/65927

  two cyclopentadienyl rings being mutually bridged · CPC title