Films incorporating polymeric material combinations, articles made therefrom, and methods of making such films and articles

Abstract

Inelastic film structures including at least one layer incorporating a combination of a first polymeric component that is at least one polymer incorporating propylene-derived units and a second polymeric component that is a thermoplastic polymer, for example, a polymer incorporating a polyolefin, are provided. The combination of the first polymeric component and the second polymeric component incorporates from about 40 wt. % to about 98 wt. % of the at least one polymer incorporating propylene-derived units and from about 2 wt. % to about 60 wt. % of the at least one polymer incorporating a polyolefin. The film structures are found to have properties making the structures useful for inclusion in a variety of applications. In certain embodiments, the film structures may exhibit optical clarity, tack, sealability, toughness, softness, and machinability properties superior to conventional polypropylene films and other conventional polyolefin films.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 and FIG. 2 illustrate in graphical form the heat seal performance of monolayer polypropylene films containing 40 wt. % to 80 wt. % Vistamaxx™ 3000.

FIG. 3 and FIG. 4 provide the heat seal performance of coextruded PP 2252 films containing 60% to 80% Vistamaxx™ 3000 in the respective skins.

Claims

1. An inelastic film comprising at least one layer incorporating a polymeric combination comprising: (i) from about 40 wt. % to about 98 wt. % of a first polymeric component that is at least one polymer comprising propylene-derived units wherein the propylene-derived units have an isotactic triad fraction of about 65% to about 99% propylene-derived units and the at least one polymer has a heat of fusion of less than 75 J/g; and(ii) from about 2 wt. % to about 60 wt. % of a second polymeric component that is at least one thermoplastic polymer;(iii) wherein the polymeric structure has a permanent set value greater than 84.9%.

2. The inelastic film of claim 1 wherein the second polymeric component comprises a polyolefin, and wherein the polymeric structure has a permanent set value of at least 100%.

3. The inelastic film of claim 2 wherein the at least one polymer comprising propylene-derived units is a copolymer comprising at least 75 wt. % of propylene-derived units.

4. The inelastic film of claim 3 wherein the at least one polymer comprising propylene-derived units comprises at least 5 wt. % of comonomer units derived from monomers other than propylene.

5. The inelastic film of claim 4 wherein the comonomer units are ethylene-derived units.

6. The inelastic film of claim 5 wherein the at least one polymer comprising propylene-derived units comprises from about 75 wt. % to about 95 wt. % propylene-derived units and from about 5 wt. % to about 25 wt. % ethylene-derived units.

7. The inelastic film of claim 6 wherein the combined weights of the first polymeric component and the second polymeric component comprise from about 60 wt. % to about 100 wt. % of the polymeric combination.

8. The inelastic film of claim 1 wherein the polymeric combination comprises about 1 wt. % to about 60 wt. % of an additive selected from the group consisting of a filler, a pigment, a coloring agent, a processing oil, a plasticizer, and mixtures thereof.

9. The inelastic film of claim 6 wherein the polymeric combination comprises about 1 wt. % to about 95 wt. % of a non-functionalized plasticizer wherein the non-functionalized plasticizer has a kinematic viscosity of at least 2 cSt at 100° C.

10. The inelastic film of claim 9 wherein the non-functionalized plasticizer has a flashpoint of at least 200° C.

11. The inelastic film of claim 10 wherein the at least one polymer comprising propylene-derived units comprises about 10 wt. % to about 20 wt. % of ethylene-derived units.

12. The inelastic film of claim 6 wherein the second component is selected from the group consisting of propylene homopolymers and copolymers and ethylene homopolymers copolymers, and combinations thereof.

13. The inelastic film of claim 6 wherein the second component is a propylene homopolymer.

14. The inelastic film of claim 6 wherein the second component is selected from the group consisting of low density polyethylene, linear low density polyethylene, and high density polyethylene.

15. The inelastic film of claim 6 wherein the film is a single layer film.

16. The inelastic film of claim 6 wherein the film comprises at least one film layer, in addition to the at least one layer incorporating a polymeric combination, comprising a metallocene catalyzed linear low density polyethylene.

17. A method for forming an inelastic film, the method comprising forming at least one layer incorporating a polymeric combination comprising: (i) from about 40 wt. % to about 98 wt. % of a first polymeric component that is at least one polymer comprising propylene-derived units wherein the propylene-derived units have an isotactic triad fraction of about 65% to about 99% propylene-derived units and the at least one polymer has a heat of fuision of less than 75 J/g; and(ii) from about 2 wt. % to about 60 wt. % of a second polymeric component that is at least one polyolefin;(iii) wherein the polymeric structure has a permanent set value of at least 100.0%.

18. The method of claim 17 wherein the at least one polymer comprising propylene-derived units is a copolymer comprising at least 75 wt. % of propylene-derived units.

19. The method of claim 18 wherein the at least one polymer comprising propylene-derived units comprises at least 5 wt. % of comonomer units derived from monomers other than propylene.

20. The method of claim 19 wherein the comonomer units are ethylene-derived units.

21. The method of claim 20 wherein the at least one polymer comprising propylene-derived units comprises from about 75 wt. % to about 95 wt. % propylene-derived units and from about 5 wt. % to about 25 wt. % ethylene-derived units.

22. The method of claim 21 wherein the combined weights of the first polymeric component and the second polymeric component comprise from about 60 wt. % to about 100 wt. % of the polymeric combination.

23. The method of claim 17 wherein the polymeric combination comprises from about 1 wt. % to about 60 wt. % of an additive selected from the group consisting of a filler, a pigment, a coloring agent, a processing oil, a plasticizer, and mixtures thereof.

24. The method of claim 17 wherein the polymeric combination comprises about 1 wt. % to about 95 wt. % of a non-functionalized plasticizer wherein the non-functionalized plasticizer has a kinematic viscosity of at least 2 cSt at 100° C.

25. The method of claim 24 wherein the non-functionalized plasticizer has a flashpoint of at least 200° C.

26. The method of claim 25 wherein the at least one polymer comprising propylene-derived units comprises about 10 wt. % to about 20 wt. % of ethylene-derived units.

27. The method of claim 21 wherein the second component is selected from the group consisting of propylene homopolymers and copolymers and ethylene homopolymers copolymers, and combinations thereof.

28. The method of claim 21 wherein the second component is a propylene homopolymer.

29. The method of claim 21 wherein the second component is selected from the group consisting of low density polyethylene, linear low density polyethylene, and high density polyethylene.

30. The method of claim 21 wherein the film is a single layer film.

31. The method of claim 21 wherein the film comprises at least one film layer, in addition to the at least one layer incorporating a polymeric combination, comprising a metallocene catalyzed linear low density polyethylene.

32. A method for forming an article from an inelastic film, comprising contacting a first inelastic film portion with a second inelastic film portion, wherein at least one of the first or second inelastic film portions is softened, allowing the first and second film portions to become adhered together, wherein the first inelastic film portion and second inelastic film portion may be part of the same or different inelastic film, and wherein the first and second inelastic film portions comprise: (i) from about 40 wt. % to about 98 wt. % of a first polymeric component that is at least one polymer comprising propylene-derived units wherein the propylene-derived units have an isotactic triad fraction of about 65% to about 99% propylene-derived units and the at least one polymer has a heat of fusion of less than 75 J/g; and(ii) from about 2 wt. % to about 60 wt. % of a second polymeric component that is at least one polyolefin;(iii) wherein the polymeric structure has a permanent set value of at least 100%.

33. An article comprising one or more inelastic films formed into a container, wherein the film comprises: (i) from about 40 wt. % to about 98 wt. % of a first polymeric component that is at least one polymer comprising propylene-derived units wherein the propylene-derived units have an isotactic triad fraction of about 65% to about 99% propylene-derived units and the at least one polymer has a heat of fusion of less than 75 J/g; and(ii) from about 2 wt. % to about 60 wt. % of a second polymeric component that is at least one polyolefin;(iii) wherein the polymeric structure has a permanent set value of at least 100%.