Producing polyolefin products with improved stiffness, toughness, and processability

Patent metadata

Field	Value
Publication number	US-9850332-B2
Application number	US-201515116250-A
Country	US
Kind code	B2
Filing date	Feb 10, 2015
Priority date	Feb 11, 2014
Publication date	Dec 26, 2017
Grant date	Dec 26, 2017

Abstract

Polymers, and systems and methods for making and using the same are described herein. A polymer includes ethylene and at least one alpha olefin having from 4 to 20 carbon atoms. The polymer has a melt index ratio (MIR) greater than about 40. The polymer also has a value for Mw1/Mw2 of at least about 2.0, wherein Mw1/Mw2 is a ratio of a weight average molecular weight (Mw) for a first half of a temperature rising elution (TREF) curve from a cross-fractionation (CFC) analysis to an Mw for a second half of the TREF curve. The polymer also has a value for Tw1−Tw2 of less than about −15° C., wherein Tw1−Tw2 is a difference of a weight average elution temperature (Tw) for the first half of the TREF curve to a Tw for the second half of the TREF curve.

First claim

What is claimed is:

1. A polymer, comprising ethylene and at least one alpha olefin having from 4 to 20 carbon atoms, wherein the polymer has:
a melt index ratio (MIR) greater than about 40;
a value for Mw1/Mw2 of at least about 2.0, wherein Mw1/Mw2 is a ratio of a weight average molecular weight (Mw) for a first half of a temperature rising elution (TREF) curve from a cross-fraction (CFC) analysis to a Mw for a second half of the TREF curve; and
a value for Tw1−Tw2 of less than about −15° C., wherein Tw1−Tw2 is a difference of a weight average elution temperature (Tw) for the first half of the TREF curve to a Tw for the second half of the TREF curve.

2. The polymer of claim 1 , wherein the polymer has:
an average modulus of greater than about 20,000 psi at 1 mil film gauge; and
a dart impact strength of greater than about 100 g/mil at 1 mil film gauge.

3. The polymer of claim 1 , wherein the polymer has no negative inflection point in a van Gurp Palmen (vGP) plot at a frequency of between about 0.1 rad/s and 300 rad/s at 190° C.

4. The polymer of claim 1 , wherein the polymer has a relationship between average modulus (M) and dart impact strength in g/mil (DIS) complying with the formula:
DIS≧0.8×[100+ e (11.71−0.000268×N+2.183×10 −9 ×M 2 ) ].

5. The polymer of claim 1 , comprising:
a lower molecular weight polymer formed by a first catalyst and a higher molecular weight polymer formed by a second catalyst, wherein:
the lower molecular weight polymer has a density of about 0.02 greater than the density of the higher molecular weight polymer; and
the mol ratio of the first catalyst to the second catalyst is between about 1:1 and 1:10.

6. The polymer of claim 5 , wherein the lower molecular weight polymer has a peak molecular weight of less than about ¼ of the peak molecular weight of the higher molecular weight polymer.

7. The polymer of claim 1 , comprising a polymer chain formed by a catalyst system comprising bis(n-propylcyclopentadienyl) hafnium (CH 3 ) 2 .

8. The polymer of claim 1 , comprising a polymer chain formed by a catalyst system comprising bis(n-butyl, methyl cyclopentadienyl) zirconium (CH 3 ) 2 .

9. The polymer of claim 1 , comprising a polymer chain formed by a catalyst system comprising bis(1-ethylindenyl) zirconium (CH 3 ) 2 .

10. The polymer of claim 1 , comprising a polymer chain formed by a catalyst system comprising any one of the compounds represented by the following formulas:

wherein R 1 and R 2 are each, independently, methyl, chloro, fluoro, or a hydrocarbyl group.

11. The polymer of claim 1 , comprising polymer chains formed by a catalyst system comprising bis(n-propylcyclopentadienyl) hafnium (CH 3 ) 2 and bis(1-ethylindenyl) zirconium (CH 3 ) 2 .

12. The polymer of claim 1 , comprising polymer chains formed by a catalyst system comprising bis(n-propylcyclopentadienyl) hafnium (CH 3 ) 2 and meso-O(SiMe 2 Ind) 2 ZrMe 2 .

13. The polymer of claim 1 , comprising polymer chains formed by a catalyst system comprising a compound represented by one of the following formulas:
Cp A Cp B MX n or Cp A (A)Cp B MX n ,

wherein M is a Group 4, 5, or 6 atom; Cp A and Cp B are each bound to M and are independently selected from the group consisting of cyclopentadienyl ligands, substituted cyclopentadienyl ligands, ligands isolobal to cyclopentadienyl and substituted ligands isolobal to cyclopentadienyl; (A) is a divalent bridging group bound to both Cp A and Cp B selected from the group consisting of divalent C 1 to C 20 hydrocarbyls and C 1 to C 20 heteroatom containing hydrocarbonyls, wherein the heteroatom containing hydrocarbonyls comprise from one to three heteroatoms; X is a leaving group selected from the group consisting of chloride ions, bromide ions, C 1 to C 10 alkyls, and C 2 to C 12 alkenyls, carboxylates, acetylacetonates, and alkoxides; and n is an integer from 1 to 3.

14. A polymer, comprising ethylene and at least one alpha olefin having 4 carbon atoms, wherein the polymer has:
a total haze of less than about 30% at 1 mil film gauge;
an average modulus of greater than about 30,000 psi at 1 mil film gauge;
a dart impact strength of greater than about 120 g for a 1 mil film;
a melt index ratio (MIR) greater than about 25; and
an Elmendorf machine direction tear of greater than about 170 g at 1 mil film gauge.

15. The polymer of claim 14 , wherein the polymer has a relationship between average modulus (M) and dart impact strength in g/mil (DIS) complying with the formula:
DIS≧0.8×[100+ e (11.71−0.000268×M+2.183×10 −9 ×M 2 ) ].

16. The polymer of claim 14 , comprising a polymer chain formed by a catalyst system comprising any one of the compounds represented by the following formulas:

wherein R 1 and R 2 are each, independently, methyl, chloro, fluoro, or a hydrocarbyl group.

17. A polymer, comprising ethylene and at least one alpha olefin having 4 carbon atoms, wherein the polymer has:
a value for melt index ratio (MIR) of between about 25 and about 35;
a value for Mw1/Mw2 of at least about 2.0, wherein Mw1/Mw2 is a ratio of a weight average molecular weight (Mw) for a first half of a temperature rising elution (TREF) curve to a Mw for a second half of the TREF curve; and
a value for Tw1−Tw2 of less than about −15° C., wherein Tw1−Tw2 is a difference of a weight average elution temperature (Tw) for the first half of the TREF curve to a Tw for the second half of the TREF curve.

Assignees

• Univation Tech Llc

Inventors

• Lue Ching-Tai
• Rix Francis C
• Boller Timothy M
• Giesbrecht Garth R
• Goode Mark G
• Kao Sun-Chueh
• Li Dongming
• Pequeno R Eric
• Farley James M
• Zilker Jr Daniel P

Classifications

• C08J5/18 Primary

  Manufacture of films or sheets · CPC title

• B32B27/32

  comprising polyolefins {(comprising vinyl (co)polymers or acrylic (co)polymers B32B27/30)} · CPC title

• C08F2500/10

  Short chain branches · CPC title

• C08F4/76

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

• C08F210/02

  Ethene · CPC title