Coextruded multilayer film with propylene-based polymer barrier layer
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 T 1c <T 2g . Layer A has an effective moisture permeability less than 0.40 g-mil/100 in 2 /day.
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 homopolymer having a melt flow rate from 1.5 g/10 min to 2.5 g/10 min and a crystallinity from 30% to 45%, and having a crystallization temperature (T 1 c) from 115° C. to less than 125° C.;
layer B comprising a second polymer selected from the group consisting of (i) a polycarbonate having a glass transition temperature (T 2 g) greater than 150° C. and (ii) a pentablock hydrogenated styrene having a T 2 g greater than 125° C.; and
layer A comprises truncated spherulites and 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 T 2 g−T 1 c is greater than 20° C.
4. 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.
5. The multilayer film of claim 1 wherein the pentablock hydrogenated styrene has a T 2 g greater than 135° C.
6. The multilayer film of claim 5 wherein T 2 g−T 1 c is greater than 20° C.
7. The multilayer film of claim 5 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.
8. The multilayer film of claim 1 wherein the core component has a thickness from 0.1 mil to 10.0 mil.
9. The multilayer film of claim 1 comprising at least one skin layer.
10. The multilayer film of claim 9 wherein the skin layers comprise a propylene-based polymer.
11. The multilayer film of claim 1 wherein the propylene homopolymer has a crystallinity from 35% to 45%.
12. 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 homopolymer having a crystallinity from 35% to 50% and having a crystallization temperature (T 1 c) from 115° C. to less than 125° C.;
layer B comprising a second polymer selected from the group consisting of (i) a polycarbonate having a glass transition temperature (T 2 g) greater than 150° C. and (ii) a pentablock hydrogenated styrene having a T 2 g greater than 125° C.; and
layer A comprises truncated spherulites and 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.
13. The multilayer film of claim 12 wherein the propylene homopolymer has a melt flow rate from 1.5 g/10 min to 2.5 g/10 min.
14. The multilayer film of claim 1 wherein the core component comprises from 30 to 300 alternating layers of layer A and layer B;
layer A has a thickness from 200 nm to 400 nm;
layer B has a thickness from 50 nm to 500 nm; and
the core component has a thickness from 0.1 mil to 10.0 mil.
15. The multilayer film of claim 1 wherein the core component has a thickness from 2.0 mil to 10.0 mil.
16. The multilayer film of claim 12 wherein the core component comprises from 30 to 300 alternating layers of layer A and layer B;
layer A has a thickness from 200 nm to 400 nm;
layer B has a thickness from 50 nm to 500 nm; and
the core component has a thickness from 0.1 mil to 10.0 mil.
17. The multilayer film of claim 12 wherein the core component has a thickness from 2.0 mil to 10.0 mil.
18. 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 homopolymer having a melt flow rate from 1.5 g/10 min to 2.5 g/10 min and a crystallinity from 30% to 45%, and having a crystallization temperature (T 1 c) from 115° C. to less than 125° C.;
layer B comprising a second polymer comprising a polycarbonate having a glass transition temperature (T 2 g) greater than 170° C.;
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.
19. The multilayer film of claim 18 wherein the core component comprises from 30 to 300 alternating layers of layer A and layer B;
layer A has a thickness from 200 nm to 400 nm;
layer B has a thickness from 50 nm to 500 nm; and
the core component has a thickness from 0.1 mil to 10.0 mil.
20. The multilayer film of claim 18 wherein the core component has a thickness from 2.0 mil to 10.0 mil.