Multilayer, halide free, retortable barrier film

• US 5,993,949 A
• Filed: 11/21/1997
• Issued: 11/30/1999
• Est. Priority Date: 11/16/1993
• Status: Expired due to Term

• Current Assignee: Baxter International Inc.
• Original Assignee: Baxter International Inc.
• Inventors: Nebgen, Gregg, Smith, Sidney T., Rosenbaum, Larry, Bacehowski, David V., Kalyankar, Varsha, Giovanetto, Steven
• Primary Examiner(s): Thlbodeau, Paul
• Assistant Examiner(s): TARAZANO, DONALD LAWRENCE
• Application Number:
  US08/975,602
• Time in Patent Office: 739 Days
• Field of Search: 428/35.4, 428/355 EN, 428/355 BL, 428/355 AC, 428/515, 428/516, 428/517, 428/520, 428/215, 428/213, 428/475.8, 428/476.1, 428/521, 428/522
• US Class Current: 428/213
• CPC Class Codes: B29C 48/08 flexible, e.g. films
• CPC Class Codes: B29C 48/185 comprising six or more components, i.e. each component being counted once for each time it is present, e.g. in a layer
• CPC Class Codes: B32B 2323/04 Polyethylene
• CPC Class Codes: B32B 2325/00 Polymers of vinyl-aromatic compounds, e.g. polystyrene
• CPC Class Codes: B32B 2377/00 Polyamides
• CPC Class Codes: B32B 2439/80 Medical packaging
• CPC Class Codes: B32B 2597/00 Tubular articles, e.g. hoses, pipes
• CPC Class Codes: B32B 27/08 of synthetic resin
• CPC Class Codes: B32B 27/302 comprising aromatic vinyl (co)polymers, e.g. styrenic (co)polymers
• CPC Class Codes: B32B 27/32 comprising polyolefins comprising vinyl (co)polymers or acrylic (co)polymers B32B27/30
• CPC Class Codes: B32B 27/34 comprising polyamides
• CPC Class Codes: B32B 7/12 using interposed adhesives or interposed materials with bonding properties
• CPC Class Codes: C08L 2203/02 for biomedical use
• CPC Class Codes: C08L 23/08 Copolymers of ethene C08L23/16 takes precedence
• CPC Class Codes: C08L 23/0815 Copolymers of ethene with aliphatic 1-olefins
• CPC Class Codes: C08L 23/0846 Copolymers of ethene with unsaturated hydrocarbons containing other atoms than carbon or hydrogen atoms
• CPC Class Codes: C08L 23/0853 Vinylacetate
• CPC Class Codes: C08L 23/0869 Acids or derivatives thereof
• CPC Class Codes: C08L 23/10 Homopolymers or copolymers of propene
• CPC Class Codes: C08L 25/04 Homopolymers or copolymers of styrene
• CPC Class Codes: C08L 2666/04 : Macromolecular compounds according to groups C08L7/00 - C08L49/00, or C08L55/00 - C08L57/00; Derivatives thereof
• CPC Class Codes: C08L 2666/20 : Macromolecular compounds having nitrogen in the main chain according to C08L75/00 - C08L79/00; Derivatives thereof
• CPC Class Codes: C08L 53/00 : Compositions of block copolymers containing at least one sequence of a polymer obtained by reactions only involving carbon-to-carbon unsaturated bonds; Compositions of derivatives of such polymers
• CPC Class Codes: C08L 53/02 : of vinyl-aromatic monomers and conjugated dienes
• CPC Class Codes: C08L 77/00 : Compositions of polyamides obtained by reactions forming a carboxylic amide link in the main chain of polyhydrazides C08L79/06; of polyamideimides or polyamide acids C08L79/08; Compositions of derivatives of such polymers
• CPC Class Codes: Y10T 428/1341 : Contains vapor or gas barrier, polymer derived from vinyl chloride or vinylidene chloride, or polymer containing a vinyl alcohol unit
• CPC Class Codes: Y10T 428/2495 : Thickness [relative or absolute]
• CPC Class Codes: Y10T 428/2878 : including addition polymer from unsaturated monomer
• CPC Class Codes: Y10T 428/2883 : including addition polymer of diene monomer [e.g., SBR, SIS, etc.]
• CPC Class Codes: Y10T 428/31743 : Next to addition polymer from unsaturated monomer[s]
• CPC Class Codes: Y10T 428/31746 : Polymer of monoethylenically unsaturated hydrocarbon
• CPC Class Codes: Y10T 428/31909 : Next to second addition polymer from unsaturated monomers
• CPC Class Codes: Y10T 428/31913 : Monoolefin polymer
• CPC Class Codes: Y10T 428/31917 : Next to polyene polymer
• CPC Class Codes: Y10T 428/31928 : Ester, halide or nitrile of addition polymer
• CPC Class Codes: Y10T 428/31931 : Polyene monomer-containing
• CPC Class Codes: Y10T 428/31935 : Ester, halide or nitrile of addition polymer

Abstract

A multiple layer structure comprising a skin layer, a barrier layer, a radio frequency susceptible layer having a first polyolefin in an amount within a range of 30-60% by weight, a second polyolefin in an amount within the range of 25-50% by weight, a radio frequency susceptible polymer in an amount within the range of 3-40% by weight, a styrene and hydrocarbon block copolymer in an amount within the range of 5-40% by weight of the sealant layer.

Claims

1. A multiple layer structure comprising:

A skin layer;

A barrier layer;

a radio frequency susceptible layer having a first polyolefin in an amount within a range of 30-60% by weight of the susceptible layer, a second polyolefin in an amount within the range of 25-50% by weight, a radio frequency susceptible polymer in an amount within the range of 3-40% by weight of the susceptible layer a styrene and hydrocarbon block copolymer in an amount within the range of 5-40% by weight of the susceptible layer; and

wherein the structure has a mechanical modulus of less than 40,000 psi when measure in accordance with ASTM D-882.

2. The structure of claim 1 wherein the barrier layer is selected from the group consisting of ethylene vinyl alcohol copolymers, and polyamides.

3. The structure of claim 2 wherein the skin layer comprises polypropylene and 0-20% by weight styrene-ethylene-butene-styrene block copolymer based on the weight of the polypropylene.

4. The structure of claim 3 wherein the first polyolefin is a polypropylene, and the second polyolefin is selected from the group consisting of ethylene copolymers, ultra low density polyethylene, polybutene-1, butene ethylene copolymers, ethylene vinyl acetate copolymers with vinyl acetate contents between 18-50%, ethylene methyl acrylate copolymers with methyl acrylate contents being between approximately 20-40%, ethylene n-butyl acrylate copolymers with n-butyl acrylate content of between 20-40%, ethylene acrylic acid copolymers with the acrylic acid content of greater than approximately 15%.

5. The structure of claim 3 wherein the radio frequency susceptible polymer is selected from the group of polyamides, ethylene vinyl acetate copolymers with vinyl acetate in an amount of 18-50% by weight, ethylene methyl acrylate copolymers with methyl acrylate in an amount between 20%-40% by weight, and ethylene vinyl alcohol copolymers with vinyl alcohol in an amount of 15%-70%.

6. The structure of claim 5 wherein the styrene and hydrocarbon block copolymer is a styrene-ethylene-butene-styrene block copolymer.

7. The structure of claim 6 further including two tie layers, one tie layer being disposed between the skin layer and the barrier layer, and the other tie layer being disposed between the barrier layer and the radio frequency susceptible layer.

8. The structure of claim 7 wherein the tie layers are selected from the group of maleic anhydride modified polyolefins, and maleic anhydride modified propylene and ethylene copolymers.

9. The structure of claim 7 wherein the radio frequency polymer is a polyamide resulting from the condensation reaction of a dimer fatty acid and a diamine.

10. The structure of claim 7 wherein the skin layer has a thickness within a range of 0.5 mil-4.0 mil, the barrier layer has a thickness within the range of 0.3 mil-5.0 mil, the radio frequency susceptible layer has a thickness within the range of 2.0 mil-8.0 mils, and the tie layers each have a thickness within the range 0.3 mil-1.0.

11. A multiple layer structure comprising:

a skin layer;

a barrier layer;

a first and a second radio frequency susceptible layer each having a first polyolefin in an amount within a range of 30-60% by weight of the susceptible layer, a second polyolefin in an amount with the range of 25-50% by weight of the susceptible layer, a radio frequency susceptible polymer in an amount within the range of 3-40% by weight of the susceptible layer, a styrene and hydrocarbon block copolymer in an amount within the range of 5-40% by weight of the susceptible layer;

a first polypropylene layer disposed between the first and the second radio frequency susceptible layers having a thickness; and

wherein the structure has a mechanical modulus of less than 40,000 psi when measured in accordance with ASTM D-882.

12. The structure of claim 11 wherein the first and second radio frequency susceptible layer are of the same thickness.

13. The structure of claim 11 wherein the first and second radio frequency susceptible layer are of different thickness.

14. The structure of claim 13 further comprising:

a first tie layer disposed between the skin layer and the barrier layer; and

a second tie layer disposed between the barrier layer and the first radio frequency susceptible layer.

15. The structure of claim 11 wherein the barrier layer is selected from the group consisting of ethylene vinyl alcohol copolymers and polyamides.

16. The structure of claim 15 wherein the first polyolefin is a polypropylene, and the second polyolefin is selected from the group consisting of ethylene copolymers, ultra low density polyethylene, polybutene-1, butene ethylene copolymers, ethylene vinyl acetate copolymers with vinyl acetate contents between 18-50%, ethylene methyl acrylate copolymers with methyl acrylate contents being between approximately 20-40%, ethylene n-butyl acrylate copolymers with n-butyl acrylate content of between 20-40%, ethylene acrylic acid copolymers with the acrylic acid content of greater than approximately 15%.

17. The structure of claim 16 wherein the skin layer comprises polypropylene and 0-20% by weight styrene-ethylene-butene-styrene block copolymer based on the weight of the polypropylene.

18. A multiple layer structure comprising:

a skin layer;

a barrier sandwich layer having from 2 to 10 units, each unit comprising a barrier sub-layer and a tie sub-layer; and

a radio frequency susceptible layer having a first polyolefin in an amount with a range of 30-60% by weight of the susceptible layer, a second polyolefin in an amount within the range of 25-50% by weight of the susceptible layer, a radio frequency susceptible polymer in an amount within the range of 3-40% by weight of the susceptible layer a styrene and hydrocarbon block copolymer in an amount within the range of 5-40% by weight of the susceptible layer.

19. The structure of claim 18 further comprising a tie layer between the skin layer and the barrier sandwich.