Coextruded Multilayer Film with Propylene-Based Polymer Barrier Layer

Patent metadata

Field	Value
Publication number	US-2016152009-A1
Application number	US-201414900481-A
Country	US
Kind code	A1
Filing date	Jun 25, 2014
Priority date	Jun 28, 2013
Publication date	Jun 2, 2016
Grant date	—

Abstract

The present disclosure provides a coextruded multi layer film. 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 nm and includes a propylene-based polymer having a crystallization temperature (T 1c ). Layer B includes a second polymer having a glass transition temperature (T 2g ), wherein l\ c<T 2g . Layer A has an effective moisture permeability less than 0.40 g-mil/100 in 2 /day.

First claim

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 100 nm to 500 nm and comprising a propylene-based polymer having a crystallization temperature (T 1 c); layer B comprising a second polymer having a glass transition temperature (T 2 g), wherein T 1 c<T 2 g; and layer A has an effective moisture permeability from 1.55 g-mil/m 2 /24 hr to less than or equal to 4.65 g-mil/m 2 /24 hr.

2 . The multilayer film of claim 1 wherein layer A has a thickness from 200 nm to 400 nm.

3 . The multilayer film of claim 1 wherein layer A comprises a propylene homopolymer with a T 1 c 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 second polymer is selected from the group consisting of a polycarbonate and a cyclic olefin polymer.

7 . The multilayer film of claim 1 wherein layer A comprises a propylene homopolymer with a T 1 c less than 125° C. and a melt flow rate from 1.5 g/10 min to 2.5 g/10 min; and
layer B comprises a polycarbonate with a T 2 g greater than 125° C.

8 . The multilayer film of claim 1 wherein T 2 g-T 1 c is greater than 20° C.

9 . The multilayer film of claim 1 wherein layer A has a thickness from 200 nm to 400 nm and layer A has an effective moisture permeability from 3.1 g-mil/m 2 /24 hr to less than or equal to 4.65 g-mil/m 2 /24 hr.

10 . The multilayer film of claim 1 wherein layer A comprises a propylene homopolymer with a T 1 c less than 125° C.; and
layer B comprises a cyclic olefin polymer with a T 2 g greater than 125° C.

11 . The multilayer film of claim 10 wherein T 2 g-T 1 c is greater than 20° C.

12 . The multilayer film of claim 10 wherein the cyclic olefin polymer is a cyclic block copolymer.

13 . The multilayer film of claim 12 wherein the cyclic block copolymer comprises a pentablock hydrogenated styrene.

14 . The multilayer film of claim 10 wherein layer A has a thickness from 200 nm to 400 nm and layer A has an effective moisture permeability from 3.1 g-mil/m 2 /24 hr to less than or equal to 4.65 g-mil/m 2 /24 hr.

15 . The multilayer film of claim 1 wherein the core component has a thickness from 0.1 mil to 10.0 mil.

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

17 . The multilayer film of claim 16 wherein the skin layers comprise a propylene-based polymer.

Assignees

• Dow Global Technologies Llc

Inventors

• Jenkins Steven R
• Lee Patrick Chang Dong
• Dooley Joseph
• Kirkpatrick Donald E
• Obi Bernard E

Classifications

• B32B2307/7246

  Water vapor barrier · CPC title

• B32B2307/726

  Permeability to liquids, absorption · CPC title

• B32B2307/704

  Crystalline · CPC title

• B32B2250/05

  5 or more layers · CPC title

• B32B27/08 Primary

  of synthetic resin · CPC title