Low density ethylene-based compositions with improved melt strength, output, and mechanical properties

Patent metadata

Field	Value
Publication number	US-9809701-B2
Application number	US-201414889168-A
Country	US
Kind code	B2
Filing date	May 21, 2014
Priority date	May 22, 2013
Publication date	Nov 7, 2017
Grant date	Nov 7, 2017

Abstract

The invention provides a composition comprising the following: A) a first ethylene-based polymer, formed by a high pressure, free-radical polymerization process, and comprising the following properties: a) a Mw(abs)/Mw(GPC)<2.2; and b) a MS versus I2 relationship: MS≧C×[(I2) D ], where C=13.5 cN/(dg/min) D , and D=−0.55, c) a melt index (I2) from 0.1 to 0.9 g/10 min; and B) a second ethylene-based polymer; and wherein the second ethylene-based polymer has a melt index (I2) from 0.1 to 4.0 g/10 min.

First claim

The invention claimed is:

1. A composition comprising the following:
A) a first ethylene-based polymer, formed by a high pressure, free-radical polymerization process, and comprising the following properties:
a) a Mw(abs)/Mw(GPC)<2.2, and
b) a MS versus I2 relationship: MS≧C×[(I2) D ], where C=13.5 cN/(dg/min) D , and D=−0.55,
c) a melt index (I2) from 0.1 to 0.9 g/10 min; and

B) a second ethylene-based polymer; and
wherein the second ethylene-based polymer has a melt index (I2) from 0.1 to 4.0 g/10 min.

2. The composition of claim 1 , wherein the first ethylene-based polymer is present in an amount greater than 0.5 weight percent, based on the sum of the weight of first ethylene-based polymer and the second ethylene-based polymer.

3. The composition of claim 1 , wherein the second ethylene-based polymer present in an amount from 10 to 95 wt %, based on weight of the composition.

4. The composition of claim 1 , wherein the second ethylene-based polymer is an ethylene/α-olefin interpolymer.

5. The composition of claim 4 , wherein the ethylene/α-olefin interpolymer is a heterogeneously branched ethylene/α-olefin interpolymer.

6. The composition of claim 1 , wherein the composition has a Melt Strength (190° C.) from 5 cN to 40 cN.

7. The composition of claim 1 , wherein the composition has a density from 0.910 to 0.925 g/cc.

8. The composition of claim 1 , wherein the composition has a melt index (I2) from 0.1 to 1.5 g/10 min.

9. The composition of claim 1 , wherein when said composition is formed into a film, via blown film process, the maximum output rate is at least 15 percent greater than the maximum output rate of a similar film formed from a similar composition, except the composition contains 100 wt % of the second ethylene-based polymer, based on the sum weight of the first ethylene-based polymer and the second ethylene-based polymer.

10. An article comprising at least one component formed from the composition of claim 1 .

11. A film comprising at least one layer formed from the composition of claim 1 .

12. The film of claim 11 , wherein the film comprises at least two layers.

13. The film of claim 11 , wherein the film has a MD shrink tension greater than 3.00 psi.

Assignees

• Dow Global Technologies Llc

Inventors

• Den Doelder Cornelis F J
• Karjala Teresa P
• Berbee Otto J
• Kardos Lori L

Classifications

• C08L23/06 Primary

  Polyethylene · CPC title

• C08L23/08 Primary

  Copolymers of ethene (C08L23/16 takes precedence) · CPC title

• C08L23/0815 Primary

  with aliphatic 1-olefins containing one carbon-to-carbon double bond · CPC title

• C08L2203/16

  used for films · CPC title

• C08L23/0807

  with unsaturated hydrocarbons only containing four or more carbon atoms · CPC title