Enhanced lubrication in polyolefin closure with polyolefin grafted cyclodextrin

• US 20050131119A1
• Filed: 12/27/2004
• Published: 06/16/2005
• Est. Priority Date: 12/10/2002
• Status: Active Grant

• Current Assignee: Verdant Technologies, Inc.
• Original Assignee: Cellresin Technologies, LLC
• Inventors: Wood, Willard E.
• Granted Patent: US 7,385,004 B2
• Time in Patent Office: Days
• US Class Current: 524/210
• CPC Class Codes: C08B 37/0012 Cyclodextrin [CD], e.g. cycle with 6 units (alpha), with 7 units (beta) and with 8 units (gamma), large-ring cyclodextrin or cycloamylose with 9 units or more; Derivatives thereof
• CPC Class Codes: C08F 210/18 with non-conjugated dienes, e.g. EPT rubbers
• CPC Class Codes: C08F 8/14 Esterification
• CPC Class Codes: C08F 8/46 Reaction with unsaturated dicarboxylic acids or anhydrides thereof, e.g. maleinisation
• CPC Class Codes: C08G 81/02 at least one of the polymers being obtained by reactions involving only carbon-to-carbon unsaturated bonds
• CPC Class Codes: C08G 81/024 Block or graft polymers containing sequences of polymers of C08C or C08F and of polymers of C08G
• CPC Class Codes: C08L 23/04 Homopolymers or copolymers of ethene
• CPC Class Codes: C08L 2666/24 Graft or block copolymers according to groups C08L51/00, C08L53/00 or C08L55/02; Derivatives thereof
• CPC Class Codes: C08L 5/16 Cyclodextrin; Derivatives thereof
• CPC Class Codes: C08L 51/06 grafted on to homopolymers or copolymers of aliphatic hydrocarbons containing only one carbon-to-carbon double bond
• CPC Class Codes: C08L 87/005 Block or graft polymers not provided for in groups C08L1/00 - C08L85/04
• CPC Class Codes: Y10T 428/13 Hollow or container type article [e.g., tube, vase, etc.]
• CPC Class Codes: Y10T 428/1352 Polymer or resin containing [i.e., natural or synthetic]
• CPC Class Codes: Y10T 428/1397 Single layer [continuous layer]
• CPC Class Codes: Y10T 428/269 including synthetic resin or polymer layer or component
• CPC Class Codes: Y10T 428/2878 including addition polymer from unsaturated monomer

Abstract

Thermoplastic polymer compositions in a closure can comprise a polymer, a modified vinyl polymer and a slip agent or polymer lubricant said modified polymer having a moiety comprising a cyclodextrin compound. The cyclodextrin compound, locked into the polymer structure, can absorb impurities, permeants, or other undesirable volatile materials. The cooperation between the lubricant, the cyclodextrin grafted onto the thermoplastic polymer and the polymer structure can provide barrier properties to a film, web or other polymer structure and a surface with substantial lubricity.

Claims

1. A thermoplastic polymer container closure composition, comprising a blend of a polyolefin resin, a closure lubricant and a chemically-modified polyolefin resin, the modified polyolefin resin comprising a polymethylene backbone comprising randomly substituted covalently bonded groups comprising a cyclodextrin compound;

wherein the cyclodextrin compound is substantially free of a compound in the central pore of the cyclodextrin ring.

2. The thermoplastic polymer composition of claim 1 wherein composition comprises about 100 parts by weight of the polyolefin resin, about 0.01 to 10 parts by weight of the modified polyolefin and about 0.05 to 4 wt % lubricant;

wherein the polyolefin comprises a melt index of about 0.5 to 100 g-10 min<sup>−

1</sup> and the modified polyolefin is derived from a polyolefin having a melt index of about 0.7 to 200 g-10 min.<sup>−

1</sup>

3. The thermoplastic polymer composition of claim 1 wherein the polyolefin comprises a melt index of about 1 to 75 g-10 min.⁻

1 and the modified polyolefin is derived from a polyolefin having a melt index of about 1 to 100 g-10 min.<sup>−

1</sup>

4. The thermoplastic polymer composition of claim 1 wherein the polyolefin comprises a polyethylene copolymer, a polypropylene copolymer or mixtures thereof.

5. The thermoplastic polymer composition of claim 1 wherein the modified polyolefin comprises a modified polyethylene, a modified polypropylene or mixtures thereof.

6. The thermoplastic polymer composition of claim 1 wherein the polymer closure comprises about 0.1 to 3 wt % of a fatty acid amide based on the composition.

7. The thermoplastic polymer composition of claim 1 wherein the fatty acid amide comprises a C_8-24 fatty acid amide, or mixtures thereof.

8. The thermoplastic polymer composition of claim 4 wherein the polyolefin comprises a poly(ethylene-co-propylene).

9. The thermoplastic polymer composition of claim 4 wherein the modified polyolefin comprises a modified poly(ethylene-co-propylene).

10. The thermoplastic polymer composition of claim 1 wherein the modified polyolefin comprises a cyclodextrin bonded to a maleic anhydride modified polyolefin wherein the polyolefin comprises about 0.02 to 5 weight percent maleic anhydride.

11. The thermoplastic polymer composition of claim 1 wherein the modified polyolefin comprises a cyclodextrin bonded to a maleic anhydride modified polyolefin wherein the polyolefin comprises about 0.02 to 2 weight percent maleic anhydride.

12. The thermoplastic polymer composition of claim 4 wherein the polyethylene comprises a low-density polyethylene.

13. The thermoplastic polymer composition of claim 4 wherein the polyethylene comprises a linear low-density polyethylene.

14. The thermoplastic polymer composition of claim 4 wherein the polyethylene comprises a high-density polyethylene.

15. The thermoplastic polymer composition of claim 1 wherein the cyclodextrin compound has a substituent substantially on at least one —

OH group at the −

2, −

3 or the −

6 position of a glucose moiety in the cyclodextrin.

16. A polyolefin closure comprising a shaped polyolefin cap, a weight of about 0.75 to 1.25 grams, the chip comprising a blend of a polyolefin resin, a closure lubricant and a modified polyolefin resin, the modified polyolefin resin comprising a polymethylene backbone having randomly substituted covalently bonded groups derived from a cyclodextrin compound, the chip comprising about 100 parts by weight of the polyolefin resin, about 0.05 to 4 parts by weight fatty acid amide lubricant and about 0.01 to 10 parts by weight of the modified polyolefin;

wherein the cyclodextrin compound is substantially free of a compound in the central pore of the cyclodextrin ring and the concentration of lubricant at the surface of the cap is greater than the concentration of lubricant in the bulk polymer precursor.

17. The closure of claim 16 wherein the polyolefin comprises a melt index of about 0.5 to 100 g-10 min.⁻

1 and the modified polyolefin is derived from a polyolefin with a melt index of 0.7 to 200 g-10 min<sup>−

1</sup>.

18. The closure of claim 16 wherein the polyolefin wherein the polyolefin comprises a melt index of about 1 to 75 g-10 min.⁻

1 and the modified polyolefin is derived from a polyolefin having a melt index of about 1 to 100 g-10 min.<sup>−

1</sup>

19. The closure of claim 16 wherein the polyolefin comprises a polyethylene copolymer, a polypropylene copolymer or mixtures thereof.

20. The closure of claim 16 wherein the modified polyolefin comprises a modified polyethylene, a modified polypropylene or mixtures thereof.

21. The closure of claim 16 wherein the lubricant comprises about 0.1 to 3 wt % of a fatty acid amide based on the composition.

22. The closure of claim 19 wherein the fatty acid amide comprises a C_10-24 fatty acid amide, or mixtures thereof.

23. The closure of claim 19 wherein the polyolefin comprises a poly(ethylene-co-propylene).

24. The closure of claim 19 wherein the modified polyolefin comprises a modified poly(ethylene-co-propylene).

25. The closure of claim 16 wherein the modified polyolefin comprises a cyclodextrin bonded to a maleic acid modified polyolefin wherein the polyolefin comprises about 0.02 to 5 weight percent maleic anhydride.

26. The closure of claim 16 wherein the modified polyolefin comprises a cyclodextrin bonded to a maleic acid modified polyolefin wherein the polyolefin comprises about 0.02 to 2 weight percent maleic anhydride.

27. The closure of claim 19 wherein the polyethylene comprises a low-density polyethylene.

28. The closure of claim 19 wherein the polyethylene comprises a linear low-density polyethylene.

29. The closure of claim 19 wherein the polyethylene comprises a high-density polyethylene.

30. The closure of claim 16 wherein the cyclodextrin compound has a substituent substantially on at least one —

OH group.

31. The closure of claim 16 wherein the cyclodextrin compound has a substituent substantially on at least one substituent at the −

2, 3 or the −

6 position of a glucose moiety.

32. A method of forming a closure, the closure having enhanced lubricity at the interface between a container and the closure, the method comprising the steps of:

(a) forming a molten thermoplastic polymer composition comprising a blend of polyolefin resin, a fatty acid amide closure lubricant and a chemically modified polyolefin resin, the modified polyolefin resin comprising a polymethylene backbone comprising randomly substituted covalently bonded groups comprising a cyclodextrin compound;

wherein the cyclodextrin compound is substantially free of a compound in the central pore of the cyclodextrin ring; and

(b) forming a closure from the molten thermoplastic wherein the closure has an increased amount of lubricant at the surface of the closure when compared to the bulk polymer precursor.

33. The thermoplastic polymer composition of claim 32 wherein composition comprises about 100 parts by weight of the polyolefin resin and about 0.01 to 10 parts by weight of the modified polyolefin;

wherein the polyolefin comprises a melt index of about 0.5 to 100 g-10 min<sup>−

1</sup> and the modified polyolefin is derived from a polyolefin having a melt index of about 0.7 to 200 g-10 min.<sup>−

1</sup>

34. The thermoplastic polymer composition of claim 32 wherein the polyolefin comprises a melt index of about 1 to 75 g-10 min.⁻

1 and the modified polyolefin is derived from a polyolefin having a melt index of about 1 to 100 g-10 min.<sup>−

1</sup>

35. The thermoplastic polymer composition of claim 32 wherein the polyolefin comprises a polyethylene, a polypropylene or mixtures thereof.

36. The thermoplastic polymer composition of claim 32 wherein the modified polyolefin comprises a modified polyethylene, a modified polypropylene or mixtures thereof.

37. The thermoplastic polymer composition of claim 32 wherein the lubricant comprises about 0.1 to 4 wt % of a fatty acid amide based on the composition.

38. The thermoplastic polymer composition of claim 32 wherein the fatty acid amide comprises a C_10-24 fatty acid amide, or mixtures thereof.

39. The thermoplastic polymer composition of claim 32 wherein the polyolefin comprises a poly(ethylene-co-propylene).

40. The thermoplastic polymer composition of claim 32 wherein the modified polyolefin comprises a modified poly(ethylene-co-propylene).

41. The thermoplastic polymer composition of claim 32 wherein the modified polyolefin comprises a cyclodextrin bonded to a maleic anhydride modified polyolefin wherein the polyolefin comprises about 0.02 to 5 weight percent maleic anhydride.

42. The thermoplastic polymer composition of claim 32 wherein the modified polyolefin comprises a cyclodextrin bonded to a maleic anhydride modified polyolefin wherein the polyolefin comprises about 0.02 to 2 weight percent maleic anhydride.

43. The thermoplastic polymer composition of claim 35 wherein the polyethylene comprises a low-density polyethylene.

44. The thermoplastic polymer composition of claim 35 wherein the polyethylene comprises a linear low-density polyethylene.

45. The thermoplastic polymer composition of claim 35 wherein the polyethylene comprises a high-density polyethylene.

46. The thermoplastic polymer composition of claim 32 wherein the cyclodextrin compound has a substituent substantially on at least one —

OH group at the −

2, −

3 or the −

6 position of a glucose moiety in the cyclodextrin.

47. The method of claim 32 wherein the closure comprises a threaded cap.

48. The method of claim 32 wherein the closure comprises a liner for a threaded cap.

49. The threaded cap of claim 47 wherein the threaded cap is adapted to a polyester container having a volume of about 250 milliliters to about 2 liters.

50. A polyolefin closure comprising a shaped polyolefin cap liner, a weight of about 0.75 to 1.25 grams, the chip comprising a blend of a polyolefin resin, a closure lubricant and a modified polyolefin resin, the modified polyolefin resin comprising a polymethylene backbone having randomly substituted covalently bonded groups derived from a cyclodextrin compound, the chip comprising about 100 parts by weight of the polyolefin resin, about 0.05 to 4 parts by weight fatty acid amide lubricant and about 0.01 to 10 parts by weight of the modified polyolefin;

wherein the cyclodextrin compound is substantially free of a compound in the central pore of the cyclodextrin ring and the concentration of lubricant at the surface of the cap liner is greater than the concentration of lubricant in the bulk polymer precursor.

51. The closure of claim 50 wherein the polyolefin comprises a melt index of about 0.5 to 100 g-10 min.⁻

1 and the modified polyolefin is derived from a polyolefin with a melt index of 0.7 to 200 g-10 min.<sup>−

1</sup>.

52. The closure of claim 50 wherein the polyolefin wherein the polyolefin comprises a melt index of about 1 to 75 g-10 min.⁻

1 and the modified polyolefin is derived from a polyolefin having a melt index of about 1 to 100 g-10 min.<sup>−

1</sup>

53. The closure of claim 50 wherein the polyolefin comprises a polyethylene copolymer, a polypropylene copolymer or mixtures thereof.

54. The closure of claim 50 wherein the modified polyolefin comprises a modified polyethylene, a modified polypropylene or mixtures thereof.

55. The closure of claim 50 wherein the lubricant comprises about 0.1 to 3 wt % of a fatty acid amide based on the composition.

56. The closure of claim 53 wherein the fatty acid amide comprises a C_10-24 fatty acid amide, or mixtures thereof.

57. The closure of claim 53 wherein the polyolefin comprises a poly(ethylene-co-propylene).

58. The closure of claim 53 wherein the modified polyolefin comprises a modified poly(ethylene-co-propylene).

59. The closure of claim 50 wherein the modified polyolefin comprises a cyclodextrin bonded to a maleic acid modified polyolefin wherein the polyolefin comprises about 0.02 to 5 weight percent maleic anhydride.

60. The closure of claim 50 wherein the modified polyolefin comprises a cyclodextrin bonded to a maleic acid modified polyolefin wherein the polyolefin comprises about 0.02 to 2 weight percent maleic anhydride.

61. The closure of claim 53 wherein the polyethylene comprises a low-density polyethylene.

62. The closure of claim 53 wherein the polyethylene comprises a linear low-density polyethylene.

63. The closure of claim 53 wherein the polyethylene comprises a high-density polyethylene.

64. The closure of claim 50 wherein the cyclodextrin compound has a substituent substantially on at least one —

OH group.

65. The closure of claim 50 wherein the cyclodextrin compound has a substituent substantially on at least one substituent at the −

2, 3 or the −

6 position of a glucose moiety.