Coextruded Multilayer Film with Propylene-Based Polymer and Ethylene-Based Polymer

• US 20160144605A1
• Filed: 06/25/2014
• Published: 05/26/2016
• Est. Priority Date: 06/28/2013
• Status: Active Grant

• Current Assignee: Dow Global Technologies LLC (Dow, Inc.)
• Original Assignee: Dow Global Technologies LLC (Dow, Inc.)
• Inventors: Jenkins, Steven R., Lee, Patrick Chang Dong, Dooley, Joseph, Kirkpatrick, Donald E., Obi, Bernard E.
• Granted Patent: US 10,336,041 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B32B 2250/05 5 or more layers
• CPC Class Codes: B32B 2250/242 All polymers belonging to those covered by group B32B27/32
• CPC Class Codes: B32B 2250/40 Symmetrical or sandwich layers, e.g. ABA, ABCBA, ABCCBA
• CPC Class Codes: B32B 2250/42 Alternating layers, e.g. ABAB(C), AABBAABB(C)
• CPC Class Codes: B32B 2307/724 Permeability to gases, adsorption
• CPC Class Codes: B32B 2439/00 Containers; Receptacles closures therefor B32B2435/00
• CPC Class Codes: B32B 2439/60 Bottles
• CPC Class Codes: B32B 2439/70 Food packaging
• CPC Class Codes: B32B 27/08 of synthetic resin
• CPC Class Codes: B32B 27/32 comprising polyolefins comprising vinyl (co)polymers or acrylic (co)polymers B32B27/30

Abstract

The present disclosure provides a coextruded multilayer films. In one embodiment, the coextruded multilayer film includes a core component having from 15 to 1000 alternating layers of layer A and layer B. Layer A has a thickness from 30 nm to 1000 nni and layer A includes a propylene-based polymer having a crystallization temperature (T_Pc). Layer B includes an ethylene-based polymer having a crystallization temperature (T_Ec), wherein T_Pc<T_Ec. Layer A has an effective moisture permeability less than 0.40 g-mil/100 in²/day.

Claims

1. A coextruded multilayer film comprising:

a core component comprising from 15 to 1000 alternating layers of layer A and layer B;

layer A having a thickness from 30 nm to 1000 nm and comprising a propylene-based polymer having a crystallization temperature (T_Pc);

layer B comprising an ethylene-based polymer having a crystallization temperature (T_Ec), wherein T_Pc<

T_Ec; and

layer A has an effective moisture permeability less than 0.40 g-mil/100 in²/day.

2. The multilayer film of claim 1 wherein layer A has a thickness from 30 nm to 500 nm.

3. The multilayer film of claim 1 wherein layer A comprises a propylene homopolymer with a T_Pc less than 125°

C.

4. The multilayer film of claim 1 wherein the propylene homopolymer has a melt flow rate from 1.5 g/10 min to 2.5 g/10 min.

5. The multilayer film of claim 1 wherein the propylene homopolymer has a crystallinity from 35% to 60%.

6. The multilayer film of claim 1 wherein the core component comprises from 60 to 70 alternating layers of layer A and layer B.

7. The multilayer film of claim 1 wherein layer B comprises a high density polyethylene (HDPE) having a density of at least 0.94 g/cc.

8. The multilayer film of claim 1 wherein the layer A has a thickness from 100 nm to 500 nm and layer A comprises a propylene homopolymer;

and

layer B comprises a high density polyethylene having a density from 0.95 g/cc to 0.97 g/cc.

9. The multilayer film of claim 1 comprising from 60 to 70 alternating layers;

layer A has a thickness from 100 nm to 400 nm and comprises a propylene homopolymer having a melt flow rate from 1.5 g/10 min to 2.5 g/10 min;

layer B comprises a HDPE with a density from 0.95 g/cc to 0.97 g/cc; and

layer A has an effective moisture permeability from 0.1 to less than or equal to 0.30 g-mil/100 in²/day.

10. The multilayer film of claim 1 comprising at least one skin layer.

11. A coextruded multilayer film comprising:

a core component comprising from 15 to 1000 alternating layers of layer A and layer B;

layer A having a thickness from 30 nm to 1000 nm and comprising an ethylene-based polymer having a crystallization temperature (T_Ec);

layer B comprising a propylene-based polymer having a crystallization temperature (T_Pc), wherein

T_Ec<

T_Pc; and

layer A has an effective moisture permeability less than 0.40 g-mil/100 in²/day.

12. The multilayer film of claim 11 wherein layer A has a thickness from 30 nm to 500 nm.

13. The multilayer film of claim 11 wherein layer A comprises a high density polyethylene (HDPE) having a density of at least 0.94 g/cc.

14. The multilayer film of claim 11 wherein layer A comprises a HDPE having a density from 0.95 g/cc to 0.97 g/cc.

15. The multilayer film of claim 11 wherein layer B comprises a propylene homopolymer.

16. The multilayer film of claim 11 wherein the propylene homopolymer has a melt flow rate from 1.5 g/10 min to 2.5 g/10 min.

17. The multilayer film of claim 11 wherein the propylene homopolymer has a crystallinity from 35% to 60%.

18. The multilayer film of claim 11 wherein the layer A has a thickness from 100 nm to 500 nm and layer A comprises a high density polyethylene having a density from 0.95 g/cc to 0.97 g/cc;

and

Layer B comprises a propylene homopolymer.

19. The multilayer film of claim 11 wherein the core component comprises from 60 to 70 alternating layers;

layer A has a thickness from 100 nm to 400 nm and comprises a HDPE with a density from 0.95 g/cc to 0.97 g/cc;

layer B comprises a propylene homopolymer; and

layer A has an effective moisture permeability from 0.01 to less than or equal to 0.30 g-mil/100 in²/day.

20. The multilayer film of claim 11 comprising skin layers.