Tie layer compositions and multilayer films incorporating the same

Patent metadata

Field	Value
Publication number	US-11110690-B2
Application number	US-201716461534-A
Country	US
Kind code	B2
Filing date	Nov 10, 2017
Priority date	Nov 16, 2016
Publication date	Sep 7, 2021
Grant date	Sep 7, 2021

Abstract

Embodiments are directed to a tie layer composition comprising functionalized polyethylene, styrene block copolymer, base polyethylene, and antioxidant co-stabilizers, wherein the antioxidant co-stabilizers comprise at least one oxygen scavenger, at least one peroxy free radical scavenger, and at least one alkyl free radical scavenger. Further embodiments are directed to multilayer films or sheets which include the tie layer composition.

First claim

The invention claimed is:

1. A tie layer composition comprising
functionalized polyethylene, styrene block copolymer, base polyethylene, and antioxidant co-stabilizers,
wherein the antioxidant co-stabilizers comprise at least one oxygen scavenger comprising a phosphite, at least two peroxy free radical scavengers comprising sterically hindered phenolics, and at least one alkyl free radical scavenger comprising an acrylate, thereby demonstrating improved adhesion and viscosity control, and
wherein the tie layer composition comprises from 3000 to 10,000 ppm of the antioxidant co-stabilizers including 1000 to 4300 ppm of the alkyl free radical scavenger.

2. The tie layer composition of claim 1 wherein the functionalized polyethylene is maleic anhydride grafted polyethylene.

3. The tie layer composition of claim 1 wherein the styrene block copolymer comprises styrene butadiene styrene.

4. The tie layer composition of claim 1 wherein the tie layer composition comprises 20 wt. % to 50 wt. % styrene block copolymer.

5. The tie layer composition of claim 1 wherein the tie layer composition comprises 5 wt. % to 25 wt. % of functionalized polyethylene.

6. The tie layer composition of claim 1 wherein the tie layer composition comprises 25 wt. % to 75 wt. % of polyethylene.

7. The tie layer composition of claim 1 wherein the styrene block copolymer of the tie layer composition comprises at least 35 wt. % of styrene monomer.

8. A multilayer film comprising at least five layers, wherein the at least 5 layers comprise:
at least one polyolefin outer layer;
at least one polystyrene outer layer;
at least one core layer disposed between the polyolefin outer layer and the polystyrene outer layer, the core layer comprising a polar polymer;
a first tie layer disposed between the polyolefin outer layer and the core layer; and
a second tie layer disposed between the polystyrene outer layer and the core layer,
wherein the first tie layer, the second tie layer, or both comprises a tie layer composition comprising
functionalized polyethylene, styrene block copolymer, base polyethylene, and antioxidant co-stabilizers,
wherein the antioxidant co-stabilizers comprise at least one oxygen scavenger comprising a phosphite, at least two peroxy free radical scavengers comprising sterically hindered phenolics, and at least one alkyl free radical scavenger comprising an acrylate, thereby demonstrating improved adhesion and viscosity control, and
wherein the tie layer composition comprises from 3000 to 10,000 ppm of the antioxidant co-stabilizers including 1000 to 4300 ppm of the alkyl free radical scavenger.

9. The multilayer film of claim 8 wherein the first tie layer and the second tie layer have a thickness of 2 to 20% of the overall thickness of the multilayer film.

10. The multilayer film of claim 8 wherein the first tie layer and the second tie layer both comprises the tie layer composition.

11. The multilayer film of claim 8 wherein the polyolefin outer layer comprises polyethylene, or a blend of polyethylene and one or more additional polyolefins.

12. The multilayer film of claim 8 wherein the polar polymer of the core layer comprises ethylene vinyl alcohol copolymer.

13. The multilayer film of claim 8 wherein the polystyrene outer layer comprises polystyrene, high impact polystyrene, blends of multiple polystyrene resins, or blends of polystyrene and polyolefin resins.

14. The tie layer composition of claim 1 wherein the tie layer composition comprises 30 wt % to 40 wt % styrene block copolymer.

15. The tie layer composition of claim 1 wherein the tie layer composition comprises 10 wt. % to 20 wt. % functionalized polyethylene.

16. The tie layer composition of claim 1 wherein the tie layer composition comprises 40 wt. % to 60 wt. % of polyethylene.

Assignees

• Dow Global Technologies Llc
• Dow Global Tech

Inventors

• Hansen Sydney E
• Walther Brian W
• Brown Hayley A
• Bawiskar Santosh S

Classifications

• B32B2307/74

  Oxygen absorber · CPC title

• B32B2307/50

  having particular mechanical properties · CPC title

• B32B27/08 Primary

  of synthetic resin · CPC title

• C08L23/0815

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

• B32B27/32

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