Functional tie-layer formulations in biaxially oriented films containing HDPE
Disclosed are compositions and methods for multilayer films, which, in one embodiment may comprise a core layer comprising at least 50 wt. % of high-density polyethylene. Further, the multilayer film may include a first skin layer consisting essentially of one or more ethylene-propylene copolymers. Further still, the multilayer film may include a second skin layer consisting essentially of one or more ethylene-propylene-butylene terpolymers. And yet further, the multilayer film may be oriented in at least one direction, and at least two layers of the multilayer film are coextruded.
1. A coextruded, biaxially oriented, multilayer film comprising:
a core layer comprising: (i) at least 50 wt. % of high-density polyethylene, (ii) linear, low-density polyethylene, and (iii) hydrocarbon resin;
a first tie layer and a second tie layer, wherein each comprises: (i) high-density polyethylene, (ii) linear, low: density polyethylene, and (iii) olefin-block copolymer in an amount ≤40 wt. % but ≥15 wt. %;
a first skin layer located adjacent to the first tie layer, wherein the first skin layer consists essentially of one or more ethylene-propylene copolymers; and
a second skin layer located adjacent to the second tie layer, wherein the second skin layer consists essentially of one or more ethylene-propylene-butylene terpolymers,
wherein the first tie layer and/or the second tie layer comprise at least 60 wt. % of the high-density polyethylene,
wherein the coextruded, biaxially oriented multilayer film has a haze of ≤7% using ASTM D1003.
2. The coextruded, biaxially oriented, multilayer film of claim 1 , further comprising one or more additives.
3. The coextruded, biaxially oriented, multilayer film of claim 1 , wherein the linear, low-density polyethylene in the first tie layer and/or the second tie layer comprises a concentration within a range from 5 wt. % through 35 wt. %.
4. The coextruded, biaxially oriented, multilayer film of claim 1 , wherein the first tie layer and/or the second tie layer comprise at least 80 wt. % high-density polyethylene.
5. The coextruded, biaxially oriented, multilayer film of claim 1 , wherein the first skin layer comprises at least 98 wt. % ethylene-polypropylene copolymers.
6. The coextruded, biaxially oriented, multilayer film of claim 1 , wherein the first skin layer and/or the second skin layer comprises at least 98 wt. % ethylene-polypropylene-butylene terpolymers.
7. The coextruded, biaxially oriented, multilayer film of claim 1 , wherein the first skin layer consists of the one or more ethylene-propylene copolymers and antiblock, optionally in a masterbatch solution.
8. The coextruded, biaxially oriented, multilayer film of claim 1 , wherein the second skin layer consists of the one or more ethylene-propylene-butylene terpolymers and antiblock, optionally in a masterbatch solution.
9. The coextruded, biaxially oriented, multilayer film of claim 1 , wherein the core layer consists of the at least 50 wt. % of high-density polyethylene, 40 wt. % or less of the linear, low-density polyethylene and the hydrocarbon resin.
10. The coextruded, biaxially oriented, multilayer film of claim 1 , wherein the core layer consists of the at least 50 wt. % of high-density polyethylene, 40 wt. % or less of the linear, low-density polyethylene, the hydrocarbon resin, and optionally, additives.
11. The coextruded, biaxially oriented, multilayer film of claim 1 , wherein haze is 5% or less using ASTM D1003.
12. The coextruded, biaxially oriented, multilayer film of claim 1 , wherein haze is 4% or less using ASTM D1003.
13. The coextruded, biaxially oriented, multilayer film of claim 1 , wherein the first skin layer consist of at least 95 wt % of the one or more ethylene-propylene copolymers and 5 wt. % or less of additives.
14. The coextruded, biaxially oriented, multilayer film of claim 1 , wherein the core further comprises 5 wt. % or less of additives.
15. The coextruded, biaxially oriented, multilayer film of claim 1 , wherein the linear, low-density polyethylene in the core layer, the first tie layer and/or the second tie layer is metallocene-catalyzed.
16. The coextruded, biaxially oriented, multilayer film of claim 1 , further comprising one or more polymeric films and/or paper products laminated to the coextruded, biaxially oriented, multilayer film.
17. The coextruded, biaxially oriented, multilayer film of claim 1 , further comprising one or more metallized layers, printable layers, adhesive layers, primer layers and/or coated layers in proximity to one or both outer surfaces of the coextruded, biaxially oriented, multilayer film.
18. A method comprising providing the coextruded, biaxially oriented, multilayer film of claim 1 , and forming a package or pouch therefrom.
19. The coextruded, biaxially oriented, multilayer film of claim 1 , further comprising surface treatment to one or both outer surfaces of the coextruded, biaxially oriented, multilayer film.
20. A coextruded, biaxially oriented, multilayer film comprising:
a core layer comprising: (i) at least 50 wt. % of high-density polyethylene, (ii) low-density polyethylene, and (iii) hydrocarbon resin;
a first tie layer and a second tie layer, wherein each comprises: (i) high-density polyethylene, (ii) low-density polyethylene, and (iii) olefin-block copolymer in an amount ≤40 wt. % but ≥15 wt. %;
a first skin layer located adjacent to the first tie layer, wherein the first skin layer consists essentially of one or more ethylene-propylene copolymers; and
a second skin layer located adjacent to the second tie layer, wherein the second skin layer consists essentially of one or more ethylene-propylene-butylene terpolymers,
wherein the first tie layer and/or the second tie layer comprise at least 60 wt. % of the high-density polyethylene,
wherein the low-density polyethylene in the core layer, the first tie layer, and/or the second tie layer: (i) comprises non-linear low-density polyethylene and/or non-metallocene-catalyzed, linear, low-density polyethylene; and/or (ii) further comprises non-linear low-density polyethylene and/or non-metallocene-catalyzed, linear, low-density polyethylene,
wherein the coextruded, biaxially oriented multilayer film has a haze of ≤7% using ASTM D1003.