Dessicant entrained polymer

• US 6,080,350 A
• Filed: 05/29/1998
• Issued: 06/27/2000
• Est. Priority Date: 04/19/1995
• Status: Expired due to Term

• Current Assignee: CSP Technologies North America LLC (AptarGroup Incorporated)
• Original Assignee: Capitol Specialty Plastics Incorporated (AptarGroup Incorporated)
• Inventors: Hekal, Ihab M.
• Primary Examiner(s): Timm, Catherine
• Assistant Examiner(s): MCDOWELL, SUZANNE E
• Application Number:
  US09/086,880
• Time in Patent Office: 760 Days
• Field of Search: 206/204, 34/95, 34/329, 502/402, 502/405, 53/400, 53/428, 53/111, 264/DIG. 78, 264/250, 264/259, 264/510, 264/173.16, 264/268, 264/165, 264/299, 264/176.1, 264/255, 252/194
• US Class Current: 264/255
• CPC Class Codes: B01D 53/261 by adsorption
• CPC Class Codes: B01D 53/28 Selection of materials for use as drying agents
• CPC Class Codes: B01J 20/28014 characterised by their form
• CPC Class Codes: B01J 20/28026 Particles within, immobilised, dispersed, entrapped in or on a matrix, e.g. a resin
• CPC Class Codes: B01J 20/28033 Membrane, sheet, cloth, pad, lamellar or mat
• CPC Class Codes: B01J 20/28035 with more than one layer, e.g. laminates, separated sheets
• CPC Class Codes: B01J 20/28042 Shaped bodies; Monolithic structures
• CPC Class Codes: B01J 20/28095 Shape or type of pores, voids, channels, ducts
• CPC Class Codes: B29C 45/16 Making multilayered or multicoloured articles B29C45/0062 takes precedence; feeding colouring materials into the injection unit B29C45/1816
• CPC Class Codes: B65D 81/264 for absorbing liquids
• CPC Class Codes: B65D 81/266 for absorbing gases, e.g. oxygen absorbers or desiccants B65D51/244, B65D51/30 take precedence
• CPC Class Codes: C08J 9/26 by elimination of a solid phase from a macromolecular composition or article, e.g. leaching out
• CPC Class Codes: F26B 21/083 by using sorbent or hygroscopic materials, e.g. chemical substances, molecular sieves
• CPC Class Codes: Y10S 264/78 Processes of molding using vacuum

Abstract

The present invention includes processes and resulting structures for producing moisture absorbing desiccant entrained polymers. A polymer is caused to assume a molten state, typically by applying heat and melting the polymer. A channeling agent is blended then reacted into the polymer so that it is distributed within the polymer. A desiccating agent is then blended into the product so that the desiccating agent is distributed within the product. The product is solidified so that the channeling agent forms passages in the product through which moisture is communicable to desiccating agent that is entrained within the product. The solidified product may be used to form plug type inserts and liners for closed containers, or it may be formed into any shaped article.

Claims

1. A process for producing a desiccant entrained polymer shaped article, the process comprising:

(a) blending a functionalized polymer and a channeling agent, wherein the channeling agent is a hydrophilic material;

(b) reacting the polymer and the channeling agent;

(c) blending a desiccant agent into the polymer-channeling agent reaction product to entrain the desiccant agent in the reaction product;

(d) solidifying the desiccant agent entrained polymer-channeling agent reaction product and forming the shaped article, whereby the channeling agent forms channels in the product.

2. The process of claim 1, wherein the polymer is selected from the group of functional polymers consisting of anhydride, amine, acid, cyanate, isocyanate and hydroxy functionalized polymers.

3. The process of claim 2, wherein the polymer is selected from the group consisting of propylene maleic anhydride, polyethylene maleic anydride, polyethylene acrylic acid, polyethylene-urethane, polyethylene-EVOH, polyethylene nylon, and polyamide.

4. The process of claim 1, wherein the channeling agent is a polar compound having one or more hydroxy groups.

5. The process of claim 4, wherein the channeling agent is selected from the group consisting of polyethylene glycol, polypropylene glycol, ethylene vinyl alcohol, polyvinyl alcohol and glycerin.

6. The process of claim 1 wherein the polymer is melted prior to blending and reacting with the channeling agent.

7. The process of claim 1 wherein the desiccating agent is a molecular sieve.

8. The process of claim 1 further comprising:

forming a plug from the product for inclusion within a container constructed of a moisture barrier substance.

9. The process of claim 8 further comprising:

depositing the plug within a container constructed from a moisture barrier substance thereby creating a desiccating container; and

coupling the plug to an interior surface of the desiccating container so that the plug is fixed relative to the container.

10. The process of claim 8 wherein the step of forming the plug further comprises:

comolding a container constructed from a moisture barrier substance with the plug so that at least a portion of said plug is exposed to an interior of the container.

11. The process of claim 1, wherein the solidified product is formed into a sheet.

12. The process of claim 11 further comprising:

combining the desiccating sheet with a barrier sheet constructed of a moisture barrier substance.

13. A desiccating insert for a closeable container comprising:

a desiccating insert configured for installation into a closeable container;

said insert constructed from the process of claim 1; and

said insert having channels extending from an exterior surface of said insert into said insert'"'"'s interior through which moisture is passable thereby exposing portions of said desiccating agent located within the interior of said insert to moisture located exteriorly to said insert for absorbing and retaining that exteriorly located moisture.

14. The process of claim 1 wherein the shaped article is selected from the group consisting of a film, sleeve and beads.

17. The article of claims 1 or 15 wherein the article is in a form of a sheet.

18. The article of claims 1 or 15, wherein the article is extruded into a shaped article.

19. The article of claims 1 or 15, wherein the desiccating agent is selected from the group consisting of a silica gel, molecular sieve and clay.

20. The article of claim 1 or 15, wherein the article is a container.

21. The article of claims 1 or 15, wherein the polymer is a thermoplastic.

22. The article of claims 1 or 15, wherein the channeling agent is selected from the group consisting of a polyglycol, glycerin, ethylene-vinyl alcohol and polyvinyl alcohol.

23. The article of claims 1 or 15, wherein the article is in the form of a disc.

24. The article of claims 1 or 15, wherein the article is in the form of a film.

25. The article of claims 1 or 15, wherein the article is in a form of a sleeve.

26. The article of claims 1 or 15, wherein the article is in a form of beads.

15. A process for producing a desiccant entrained polymer shaped article, the process comprising:

(a) blending an desiccant agent, a channeling agent, wherein the channeling agent is a hydrophilic material, and a functionalized polymer;

(b) reacting the blend to form the desiccant agent entrained polymer;

(c) solidifying the desiccant agent entrained polymer to form a shaped article having channels formed by the channeling agent.

16. The process of claim 15, wherein the polymer is selected from the group of functional polymers consisting of anhydride, amine, acid, cyanate, isocyanate and hydroxy functionalized polymers.