Polyethylene compositions and films prepared therefrom

Patent metadata

Field	Value
Publication number	US-11274196-B2
Application number	US-201816632177-A
Country	US
Kind code	B2
Filing date	Jun 22, 2018
Priority date	Aug 4, 2017
Publication date	Mar 15, 2022
Grant date	Mar 15, 2022

Abstract

A polyethylene composition comprising from about 0.5 to about 20 wt % of alpha-olefin derived units other than ethylene-derived units, with the balance including ethylene-derived units, total internal unsaturations (Vy1+Vy2+T1) of from about 0.10 to about 0.40 per 1000 carbon atoms, an MI of from about 0.1 to about 6 g/10 min, an HLMI of from about 5.0 to about 40 g/10 min, a density of from about 0.890 to about 0.940 g/ml, a Tw 1 -Tw 2 value of from about −25 to about −20° C., an Mw 1 /Mw 2 value of from about 1.2 to about 2.0, an Mw/Mn of from about 4.5 to about 12, an Mz/Mw of from about 2.0 to about 3.0, an Mz/Mn of from about 7.0 to about 20, and a g′ (vis) greater than 0.90.

First claim

What is claimed is:

1. A polyethylene composition comprising:
from about 80 wt % to about 99.5 wt % ethylene-derived units; and
from about 0.5 to about 20 wt % of alpha-olefin derived units other than ethylene-derived units;
wherein the composition has total internal unsaturations (Vy1+Vy2+T1) of from about 0.10 to about 0.40 per 1000 carbon atoms, an MI of from about 0.1 to about 6 g/10 min, an HLMI of from about 5.0 to about 40 g/10 min, a density of from about 0.890 to about 0.940 g/ml, a Tw 1 -Tw 2 value of from about −25 to about −20° C., an Mw 1 /Mw 2 value of from about 1.2 to about 2.0, an Mw/Mn of from about 4.5 to about 12, an Mz/Mw of from about 2.0 to about 3.0, an Mz/Mn of from about 7.0 to about 20, and a g′ (vis) greater than 0.90.

2. The polyethylene composition of claim 1 , where said polyethylene composition has a density of from about 0.912 to about 0.917 g/ml.

3. The polyethylene composition of claim 1 , wherein the polyethylene composition has an MIR, defined as the ratio of high load melt index (HLMI, determined per ASTM D1238, 190° C., 21.6 kg load)) to melt index (MI, determined per ASTM D1238, 190° C., 2.16 kg load), of from about 20 to about 40 and an HLMI of from about 7.0 to about 35 g/10 min.

4. The polyethylene composition of claim 1 , wherein the polyethylene composition has a Tw 1 -Tw 2 value of from about −24 to about −20.5° C., an Mw 1 /Mw 2 value of from about 1.35 to about 1.85, an Mw/Mn of from about 4.7 to about 12, an Mz/Mw of from about 2.2 to about 2.9, an Mz/Mn of from about 10 to about 18, and a g′ (vis) greater than 0.92.

5. The polyethylene composition of claim 1 , wherein the polyethylene composition has a Tw 1 -Tw 2 value of from about −23 to about −21° C., an Mw 1 /Mw 2 value of from about 1.5 to about 1.8, an Mw/Mn of from about 4.4 to about 9.5, an Mz/Mw of from about 2.3 to about 2.8, an Mz/Mn of from about 11 to about 17, and a g′ (vis) greater than 0.94.

6. The polyethylene composition of claim 1 any of claims 1 to 5 , wherein the polyethylene composition has tri-substituted olefins (T1) of from about 0.08 to about 0.35 per 1000 carbon atoms.

7. The polyethylene composition of claim 1 any of claims 1 to 6 , wherein the polyethylene composition has internal unsaturations without carbon substitutions (Vy1+Vy2) of from about 0.02 to about 0.1 per 1000 carbon atoms.

8. The polyethylene composition of claim 7 , where said polyethylene composition is characterized by internal unsaturations without carbon substitutions (Vy1+Vy2) of from about 0.04 to about 0.08 per 1000 carbon atoms.

9. A blown polyethylene film comprising:
a polyethylene composition comprising from about 0.5 to about 20 wt % of alpha-olefin derived units other than ethylene-derived units, with the balance including ethylene-derived units, total internal unsaturations (Vy1+Vy2+T1) of from about 0.10 to about 0.40 per 1000 carbon atoms, an MI of from about 0.1 to about 6 g/10 min, an HLMI of from about 5.0 to about 40 g/10 min, a density of from about 0.890 to about 0.940 g/ml, a Tw 1 -Tw 2 value of from about −25 to about −20° C., an Mw 1 /Mw 2 value of from about 1.2 to about 2.0, an Mw/Mn of from about 4.5 to about 12, an Mz/Mw of from about 2.0 to about 3.0, an Mz/Mn of from about 7.0 to about 20, and a g′ (vis) greater than 0.90;
wherein the blown film has a Dart Drop Impact (DI) that is greater than 300 g/mil, a haze of less than 30%, and a machine-direction tear resistance that is greater than 120 g/mil.

10. The blown film of claim 9 , wherein the blown film has a Dart Drop Impact (DI) that is greater than 400 g/mil, a haze of less than 20%, and a machine-direction tear resistance that is greater than 130 g/mil.

11. The blown film of claim 9 , wherein the polyethylene composition has a density of from 0.914 to 0.917 g/ml, and where the film has a 1% secant modulus, in the transverse direction, of greater than 30,000 psi.

12. The blown film of claim 11 , wherein the polyethylene composition has a density of from 0.914 to 0.917 g/ml, and where the film has a 1% secant modulus, in the transverse direction, of greater than 32,000 psi.

13. The blown film of claim 9 , wherein the polyethylene composition has a density of from about 0.918 to about 0.921 g/ml, and where the film has a 1% secant modulus, in the transverse direction, of greater than 42,000 psi.

14. The blown film of claim 13 , wherein the polyethylene composition has a density of from about 0.918 to about 0.921 g/ml, and where the film has a 1% secant modulus, in the transverse direction, of greater than 45,000 psi.

15. The blown film of claim 9 , wherein the polyethylene composition has a density from about 0.912 to about 0.917 g/ml.

16. The blown film of claim 9 , wherein the polyethylene composition has an MIR, defined as the ratio of high load melt index (HLMI, determined per ASTM D1238, 190° C., 21.6 kg load) to melt index (MI, determined per ASTM D1238, 190° C., 2.16 kg load), of from about 20 to about 40 and an HLMI of from about 7.0 to about 35 g/10 min.

17. The blown film of claim 9 , wherein the polyethylene composition has a Tw 1 -Tw 2 value of from about −24 to about −20.5° C., an Mw 1 /Mw 2 value of from about 1.35 to about 1.85, an Mw/Mn of from about 4.7 to about 12, an Mz/Mw of from about 2.2 to about 2.9, an Mz/Mn of from about 10 to about 18, and a g′ (vis) greater than 0.92.

18. The blown film of claim 9 , wherein the polyethylene composition has a Tw 1 -Tw 2 value of from about −23 to about −21° C., an Mw 1 /Mw 2 value of from about 1.5 to about 1.8, an Mw/Mn of from about 4.9 to about 9.5, an Mz/Mw of from about 2.3 to about 2.8, an Mz/Mn of from about 11 to about 17, and a g′ (vis) greater than 0.94.

19. The blown film of claim 9 , wherein the polyethylene composition has tri-substituted olefins (T1) of from about 0.08 to about 0.35 per 1000 carbon atoms.

20. The blown film of claim 9 , wherein the polyethylene composition has internal unsaturations without carbon substitutions (Vy1+Vy2) of from about 0.02 to about 0.1 per 1000 carbon atoms.

21. The blown film of claim 20 , wherein the polyethylene composition has internal unsaturations without carbon substitutions (Vy1+Vy2) of from about 0.04 to about 0.08 per 1000 carbon atoms.

22. The blown film of claim 9 , where the polyethylene composition is prepared by combining a catalyst system with ethylene and an alpha-olefin comonomer other than ethylene, where the catalyst system includes (i) an unbridged hafnium metallocene compound; (ii) an unbridged zirconium metallocene compound; (iii) a support material; and (iv) activator.

23. The blown film of claim 22 , where the catalyst system includes an unbridged bis-cyclopentadienyl hafnium catalyst, an unbridged bis-cyclopentadienyl zirconium catalyst, and an activator, with ethylene and within the range from 0.1 to 5 wt % relative to the weight of all monomers of a C3 to C12 α-olefin at a temperature within the range from 60 to 100° C., wherein the unbridged zirconium metallocene is represented by the following formula (A):

where M* is hafnium; each of R 1 , R 2 , R 4 and R 5 is independently hydrogen, alkoxide, or C 1 to C 40 substituted or unsubstituted hydrocarbyl; R 3 is —R 11 —SiR′ 3 , where R 11 is a C 1 to C 4 hydrocarbyl, and each R′ is independently hydrogen or a C 1 to C 20 substituted or unsubstituted hydrocarbyl; each R 6 , R 7

Assignees

• Exxonmobil Chemical Patents Inc

Inventors

• Li Dongming
• Lue Ching-Tai
• Silva Adriana S
• Holtcamp Matthew W
• Mccullough Laughlin G
• Sanders David F
• Bedoya Matthew S

Classifications

• C08F4/65925

  two cyclopentadienyl rings being mutually non-bridged · CPC title

• C08F4/65927

  two cyclopentadienyl rings being mutually bridged · CPC title

• C08L2203/16

  used for films · CPC title

• C08F2420/07

  Heteroatom-substituted Cp, i.e. Cp or analog where at least one of the substituent of the Cp or analog ring is or contains a heteroatom · CPC title

• C08F210/14

  Monomers containing five or more carbon atoms · CPC title