Coextruded multilayer film with filler in transport layer

• US 10,160,186 B2
• Filed: 08/25/2015
• Issued: 12/25/2018
• Est. Priority Date: 08/26/2014
• Status: Active Grant

• Current Assignee: Dow Global Technologies LLC (Dow, Inc.)
• Original Assignee: Dow Global Technologies LLC (Dow, Inc.)
• Inventors: Menning, Bruce A., McGee, Robert L., Lee, Patrick Chang Dong, Patel, Rajen M.
• Primary Examiner(s): Branch, Catherine S
• Application Number:
  US15/505,426
• Publication Number:
  US 20170239921A1
• Time in Patent Office: 1,218 Days
• Field of Search: None
• CPC Class Codes: B32B 2307/724 Permeability to gases, adsorption
• CPC Class Codes: B32B 2410/00 Agriculture-related articles
• CPC Class Codes: B32B 2439/70 Food packaging
• CPC Class Codes: B32B 27/08 of synthetic resin
• CPC Class Codes: B32B 27/20 using fillers, pigments, thixotroping agents
• CPC Class Codes: B32B 27/205 the fillers creating voids or cavities, e.g. by stretching
• CPC Class Codes: B32B 27/306 comprising vinyl acetate or vinyl alcohol (co)polymers
• CPC Class Codes: B32B 27/308 comprising acrylic (co)polymers
• 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 film. The coextruded multilayer film includes a core component having from 10 to 1000 alternating layers of layer A and layer B. Layer A has a thickness from 30 nm to 1000 nm and includes a polymer selected from an ethylene/a-olefin copolymer, an ethylene vinyl acetate polymer (EVA), an ethylene methyl-acrylate copolymer (EMA), an ethylene n-butyl acetate polymer (EnBA), and combinations thereof. Layer B has a thickness from 30 nm to 1000 nm. Layer B is a blend composed of (i) a polymer selected from an ethylene-based polymer, an EVA, an EMA, an EnBA, and combinations thereof, and (ii) a particulate filler material. The core component has a water vapor transmission rate from 50 to less than 500 g-mil/m2/24 hr and a carbon dioxide transmission rate from 50,000 to 300,000 cc-mil/m2/24 hr/atm.

Claims

1. A coextruded multilayer film comprising:

a core component comprising from 10 to 1000 alternating layers of layer A and layer B;

layer A having a thickness from 30 nm to 1000 nm and comprising a polymer selected from the group consisting of an ethylene/α

-olefin copolymer, an ethylene vinyl acetate polymer (EVA), an ethylene methyl-acrylate polymer (EMA), an ethylene n-butyl acetate polymer (EnBA), and combinations thereof;

layer B comprising a blend composed of (i) a polymer selected from the group consisting of an ethylene-based polymer, an EVA, an EMA, an EnBA, and combinations thereof, and (ii) a particulate filler material; and

the core component has a water vapor transmission rate (WVTR) from 50 to less than 500 g-mil/m²/24 hr and a carbon dioxide transmission rate (CO₂TR) from 50,000 to 300,000 cc-mil/m²/24 hr/atm.

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 B has a thickness from 30 nm to 500 nm.

4. The multilayer film of claim 1 wherein the core component comprises from 100 to 200 alternating layers of layer A and layer B.

5. The multilayer film of claim 1 wherein the core component has from 50 to 150 alternating layers of layer A and layer B and the film has a WVTR from 50 to 100 g-mil/m²/24 hr and a CO₂TR from 50,000 to 100,000 cc-mil/m²/24 hr/atm.

6. The multilayer film of claim 1 wherein the particulate filler material has an average particle size, D50, from 1 micron to 10 microns.

7. The multilayer film of claim 1 comprising skin layers composed of a blend of ethylene vinyl acetate polymer and an ethylene-based polymer.

8. The multilayer film of claim 1 wherein the multilayer film has a WVTR from 50 to 100 g-mil/m²/24 hr and a CO₂TR from 50,000 to 100,000 cc-mil/m²/24 hr/atm.

9. The multilayer film of claim 7 wherein the skin layer blend further comprises a filler.

10. The multilayer film of claim 9 wherein the multilayer film has a WVTR from 60 to 100 g-mil/m²/24 hr and a CO₂TR from 60,000 to 100,000 cc-mil/m²/24 hr/atm.

11. An article comprising the multilayer film of claim 1.

12. The article of claim 11 wherein the article is a package and the multilayer film is a component of a peel seal.