Reversible chain-transfer in polyolefin polymerization with pyridyldiamide catalysts

Patent metadata

Field	Value
Publication number	US-9249238-B2
Application number	US-201414195634-A
Country	US
Kind code	B2
Filing date	Mar 3, 2014
Priority date	Mar 6, 2013
Publication date	Feb 2, 2016
Grant date	Feb 2, 2016

Abstract

A process of producing ethylene α-olefin copolymers, especially ethylene block copolymers, comprising contacting ethylene and a C 3 to C 10 α-olefin with a transition metal pyridyldiamide (MPN3) catalyst component and an activator, as well as from 10 equivalents to 1000 equivalents relative to the catalyst component of chain transfer agent; isolating an ethylene-α-olefin copolymer having a T m of less than 140° C., a MWD of less than 2.5, and a weight average molecular weight (Mw) within the range of from 5 kDa to 500 kDa. The chain transfer agent can be selected from Group 2, 12 or Group 13 alkyl or aryl compounds.

First claim

The invention claimed is:

1. A process of producing ethylene α-olefin copolymers comprising:
contacting ethylene and a C 3 to C 10 α-olefin with a transition metal pyridyldiamide catalyst component and an activator, as well as from 10 equivalents to 1000 equivalents relative to the catalyst component of chain transfer agent;
isolating an ethylene-α-olefin copolymer having a T m of less than 140° C., a Mw/Mn of less than 2.5, and a weight average molecular weight (Mw) within the range of from 5 kDa to 500 kDa, wherein the contacting first takes place in the absence of the chain transfer agent and ethylene-α-olefin copolymer is first isolated having a weight average molecular weight (Mw) within the range of greater than 200 kDa; followed by addition of the chain transfer agent and isolation of ethylene-α-olefin copolymer having a Mw of less than 400 kDa.

2. The process of claim 1 , wherein the transition metal pyridyldiamide catalyst component is selected from compounds of the following structural formula:

wherein M is a Group 4 transition metal, and each R group is selected independently from hydrogen or alkyls or aryls, and wherein any adjacent R groups may form an aliphatic or aromatic ring; and X is a halogen or alkyl.

3. The process of claim 1 , wherein the transition metal pyridyldiamide catalyst component is selected from the following structural formula:

wherein M is a Group 4 transition metal;
R 1 and R 11 are independently selected from the group consisting of hydrocarbyls, substituted hydrocarbyls, heterohydrocarbyls, and silyl groups;
R 2 and R 10 are each, independently, divalent hydrocarbyls or aryls;
R 3 , R 4 , and R 5 are independently selected from the group consisting of hydrogen, hydrocarbyls, substituted hydrocarbyls, alkoxy, aryloxy, halogen, amino, and silyl, and wherein adjacent R groups may be joined to form a substituted or unsubstituted hydrocarbyl or heterocyclic ring, where the ring has 5, 6, 7, or 8 ring atoms and where substitutions on the ring can join to form additional rings;
X is an anionic leaving group, where the X groups may be the same or different and any two X groups may be linked to form a dianionic leaving group;
Z is —(R 14 ) p QJ(R 15 ) q —, wherein Q is carbon, oxygen, nitrogen, or silicon, and where J is carbon or silicon, p is 1 or 2; and q is 1 or 2; and R 14 and R 15 are independently selected from the group consisting of hydrogen, hydrocarbyls, and substituted hydrocarbyls, and wherein adjacent R 14 and R 15 groups may be joined to form an aromatic or saturated, substituted or unsubstituted hydrocarbyl ring, where the ring has 5, 6, 7, or 8 ring carbon atoms and where substitutions on the ring can join to form additional rings.

4. The process of claim 3 , wherein R 3 , R 4 , and R 5 are independently selected from the group consisting of hydrogen, alkyls, aryls, and heteroaryls.

5. The process of claim 3 , wherein R 14 and R 15 are independently selected from the group consisting of alkyls.

6. The process of claim 1 , wherein the transition metal pyridyldiamide catalyst component is selected from the following structural formula:

wherein M is a Group 4 transition metal;
R 1 and R 11 are independently selected from the group consisting of hydrocarbyls, substituted hydrocarbyls, heterohydrocarbyls, and silyl groups;
R 2 and R 10 are each, independently, divalent C 1 to C 4 hydrocarbyls or C 5 to C 12 aryls;
R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , are independently selected from the group consisting of hydrogen, hydrocarbyls, substituted hydrocarbyls, alkoxy, aryloxy, halogen, amino, and silyl, and wherein adjacent R groups may be joined to form a substituted or unsubstituted hydrocarbyl or heterocyclic ring, where the ring has 5, 6, 7, or 8 ring atoms and where substitutions on the ring can join to form additional rings; and
X is an anionic leaving group, where the X groups may be the same or different and any two X groups may be linked to form a dianionic leaving group.

7. The process of claim 6 , wherein R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , are independently selected from the group consisting of alkyls, aryls, and heteroaryls.

8. The process of claim 1 , wherein the transition metal pyridyldiamide catalyst component is selected from compounds of the following structural formula:

wherein each R group is selected from methyl, ethyl, propyl, isopropyl, isobutyl, or tert-butyl; and X is a halogen or alkyl.

9. The process of claim 1 , wherein one transition metal pyridyldiamide catalyst component is used.

10. The process of claim 1 , wherein the chain transfer agent is selected from Group 2, 12 or Group 13 alkyl or aryl compounds.

11. The process of claim 1 , wherein the chain transfer agent is selected from diphenyl zinc or dialkyl zinc compounds, where the alkyl is selected independently from methyl, ethyl, propyl, butyl, isobutyl, tertbutyl, pentyl, hexyl, or cyclohexyl.

12. The process of claim 1 , wherein the chain transfer agent is diethylzinc.

13. The process of claim 1 , wherein the activator is a compound(s) distinguishable from the chain transfer agent.

14. The process of claim 1 , wherein the activator is a compound(s) distinguishable from the chain transfer agent and the chain transfer agent is diphenylzinc or dialkylzinc.

15. The process of claim 1 , further comprising scavenger, where the scavenger is not the same chemical compound as the chain transfer agent.

16. The process of claim 10 , wherein the presence of the chain transfer agent increases the activity of the catalyst component by a factor of at least 2 relative to the activity under the same conditions when chain transfer agent is not present.

17. The process of claim 1 , wherein the presence of the chain transfer agent increases the activity (g/mmol/h/bar) of the catalyst component by a factor of at least 3 relative to the activity under the same conditions when chain transfer agent is not present.

18. The process of claim 12 , wherein the presence of the chain transfer agent increases the activity (g/mmol/h/bar) of the catalyst component by a factor of at least 5 relative to the activity under the same conditions when chain transfer agent is not present.

19. A process of producing ethylene α-olefin copolymers comprising:
contacting ethylene and a C 3 to C 10 α-olefin with a transition metal pyridyldiamide catalyst component and an activator, as well as from 10 equivalents to 1000 equivalents relative to the catalyst component of chain transfer agent;
isolating an ethylene-α-olefin copolymer having a T m of less than 140° C., a Mw/Mn of less than 2.5, and a weight average molecular weight (Mw) within the range of from 5 kDa to 500 kDa, wherein the contacting first takes place in the absence of the chain transfer agent and ethylene-α-olefin copolymer is first isolated having a Mw/Mn within the range of from 1.5 to 2.5; followed by addition of the chain transfer agent and isolation of ethylene-α-olefin copolymer having a Mw/Mn of less than 2.0.

20.

Assignees

• Exxonmobil Chem Patents Inc

Inventors

• Hagadorn John R
• Yang Jian
• Palafox Patrick J

Classifications

• C08F4/50 Primary

  selected from alkaline earth metals, zinc, cadmium, mercury, copper or silver · CPC title

• C08F210/16

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

• C08F4/62148

  NN(R)N · CPC title

• C08F4/76 Primary

  selected from titanium, zirconium, hafnium, vanadium, niobium or tantalum · CPC title

• C08F4/52

  selected from boron, aluminium, gallium, indium, thallium or rare earths (C08F4/14 takes precedence) · CPC title