Catalyst systems and processes for producing polyethylene using the same

Patent metadata

Field	Value
Publication number	US-12428502-B2
Application number	US-202118000038-A
Country	US
Kind code	B2
Filing date	May 28, 2021
Priority date	May 29, 2020
Publication date	Sep 30, 2025
Grant date	Sep 30, 2025

Abstract

Embodiments of the present application are directed to procatalysts, and catalyst systems including procatalysts, including a metal-ligand complex having the structure of formula (I):

First claim

The invention claimed is:

1. A process for producing an ethylene-based copolymer having a reverse comonomer distribution, the process comprising polymerizing ethylene and one or more (C 3 -C 12 )α-olefin comonomers in the presence a catalyst system in a single gas-phase polymerization reactor at a reactor temperature of 60° C. to less than or equal to 150° C. and a molar feed ratio of less than or equal to 0.020 of the one or more (C 3 -C 12 )α-olefin comonomers to the ethylene, wherein:
the catalyst system comprises one or more support materials and an activated metal-ligand complex having a structure according to formula (Ia):

wherein:
A − is an anion;
M is titanium, zirconium, or hafnium;
n is 1, 2, or 3;
each X is a monodentate ligand independently chosen from unsaturated (C 2 -C 50 )hydrocarbon, unsaturated (C 2 -C 50 )heterohydrocarbon, (C 1 -C 50 )hydrocarbyl, (C 1 -C 50 )heterohydrocarbyl, (C 6 -C 50 )aryl, (C 4 -C 50 )heteroaryl, halogen, —N(R N ) 2 , and —N(R N )COR C ;
each Z is independently chosen from —O—, —S—, (C 6 -C 50 )aryl, (C 4 -C 50 )heteroaryl, N(C 1 -C 40 )hydrocarbyl, and P(C 1 -C 40 )hydrocarbyl;
R 1 and R 16 are independently chosen from (C 6 -C 50 )aryl, (C 4 -C 50 )heteroaryl, (C 1 -C 40 )alkyl, (C 3 -C 40 )heteroalkyl, radicals having formula (II), radicals having formula (III), and radicals having formula (IV):

wherein R 31-35 , R 41-48 , and R 51-59 are independently chosen from —H, (C 1 -C 50 )hydrocarbyl, (C 1 -C 50 )heterohydrocarbyl, —Si(R C ) 3 , —Ge(R C ) 3 , —P(R P ) 2 , —N(R N ) 2 , —OR C , —SR C , —NO 2 , —CN, —CF 3 , R C S(O)—, R C S(O) 2 —, (R C ) 2 C═N—, R C C(O)O—, R C OC(O)—, R C C(O)N(R N )—, (R C ) 2 NC(O)—, or halogen;

R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , R 10 , R 11 , R 12 , R 13 , R 14 , and R 15 are independently chosen from —H, (C 1 -C 50 )hydrocarbyl, (C 1 -C 50 )heterohydrocarbyl, —Si(R C ) 3 , —Ge(R C ) 3 , —P(R P ) 2 , —N(R N ) 2 , —OR C , —SR C , —NO 2 , —CN, —CF 3 , R C S(O)—, R C S(O) 2 —, (R C ) 2 C═N—, R C C(O)O—, R C OC(O)—, R C C(O)N(R)—, (R C ) 2 NC(O)—, and halogen;
R 17 and R 18 are independently chosen from —(CR C 2 ) m —, wherein subscript m is from 1 to 10;
R 19 and R 20 are independently chosen from linear or branched (C 1 -C 20 )alkyl; and
each R C , R P , and R N are independently chosen from —H, (C 1 -C 50 )hydrocarbyl, and (C 1 -C 50 )heterohydrocarbyl; and
the ethylene-based copolymer has a unimodal molecular weight distribution as determined by gel permeation chromatography (GPC) and a molecular weight comonomer distribution index of greater than 0 as determined by determined by rapid Fourier Transform-Infrared (FT-IR) spectroscopy on dissolved copolymer during the gel permeation chromatography (GPC) measurement.

2. The process of claim 1 , wherein R 1 and R 16 are the same.

3. The process of claim 1 , wherein at least one of R 1 and R 16 is a radical having formula (II) and at least one of R 32 and R 34 is tert-butyl.

4. The process of claim 1 , wherein at least one of R 1 and R 16 is a radical having formula (III).

5. The process of claim 4 , wherein at least one of R 42 , R 43 , R 46 , and R 47 is tert-butyl.

6. The process of claim 5 , wherein R 41-48 are —H.

7. The process of claim 1 , wherein the one or more support materials comprise fumed silica.

8. The process of claim 1 , wherein the catalyst system comprises spray-dried particles.

9. The process of claim 1 , wherein the process produces greater than or equal to 2,500 grams of the ethylene-based copolymer per gram of the catalyst system per hour.

10. The process of claim 1 , wherein a ratio of a weight average molecular weight of the ethylene-based copolymer to weight percent comonomer content of the ethylene-based copolymer is greater than or equal to 10,000; or wherein a ratio of a weight average molecular weight of the ethylene-based copolymer to weight percent comonomer content of the ethylene-based copolymer is greater than or equal to 20,000; or wherein a ratio of a weight average molecular weight of the ethylene-based copolymer to weight percent comonomer content of the ethylene-based copolymer is greater than or equal to 30,000.

11. The process of claim 1 , wherein the catalyst system further comprises one or more activators.

12. The process of claim 11 , wherein the one or more activators comprises methylalumoxane (MAO).

13. The process of claim 1 , wherein the catalyst system is fed to the gas-phase polymerization reactor in neat form, as a solution, as a slurry, or a combination thereof.

14. The process of claim 1 , wherein the reactor temperature is less than or equal to 120° C.; or wherein the reactor temperature is 75° C. to 105° C.; or wherein the reactor temperature is 80° C. to 100° C.; or wherein the reactor temperature is 85° C. to 95° C.

15. The process of claim 1 , wherein the molecular weight of the ethylene-based copolymer is greater than 200,000 g/mol; or wherein the ethylene-based copolymer comprises a molecular weight of greater than 500,000 g/mol.

16. The process of claim 1 , wherein the ethylene-based copolymer further comprises a comonomer incorporation of less than 30 wt. % as determined by Rapid FT-IR spectroscopy on dissolved polymer of a GPC measurement.

17. A process for producing an ethylene-based copolymer having a reverse comonomer distribution, the process comprising polymerizing ethylene and one or more (C 3 -C 12 )α-olefin comonomers in the presence a catalyst system in a single gas-phase polymerization reactor at a reactor temperature of less than or equal to 150° C. and a molar feed ratio of less than or equal to 0.020 of the one or more (C 3 -C 12 )α-olefin comonomers to the ethylene, wherein:
the catalyst system comprises an activated metal-ligand complex having a Group IV metal center and at least one dianionic heterohydrocarbyl ligand and one or more monoanionic hydrocarbyl ligand provided that the ligand is not cyclopentadienyl; wherein the catalyst system does not contain a support material; and
the ethylene-based copolymer has a unimodal molecular weight distribution and a molecular weight comonomer distribution index of greater than 0.

Assignees

• Dow Global Technologies Llc

Inventors

• Baillie Rhett A
• Do Hien Q
• Pearson David M
• Delorbe Johnathan E
• Camelio Andrew M
• Fontaine Philip P

Classifications

• C08F4/64186

  Dianionic ligand · CPC title

• C08F4/64068

  Dianionic ligand · CPC title

• C08F4/648

  inorganic · CPC title

• C08F4/642

  Component covered by group C08F4/64 with an organo-aluminium compound {(C08F4/64003 - C08F4/64196 take precedence)} · CPC title

• C08F4/76

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