Responsive polymer networks and methods of their use

• US 5,939,485 A
• Filed: 01/03/1996
• Issued: 08/17/1999
• Est. Priority Date: 06/19/1995
• Status: Expired due to Fees

• Current Assignee: Advanced Medical Solutions (Plymouth) Ltd.
• Original Assignee: Medlogic Global Corp. (Advanced Medical Solutions Group Plc)
• Inventors: McKinney, George, Lupton, Elmer Cornelius (E.C.), Timm, Mary Jo (M.J.), Bromberg, Lev, Schiller, Matthew E.
• Primary Examiner(s): Lipman, Bernard
• Application Number:
  US08/580,986
• Time in Patent Office: 1,322 Days
• Field of Search: 524/556, 524/558
• US Class Current: 524/556
• CPC Class Codes: A41C 3/10 with stiffening or bust-forming inserts
• CPC Class Codes: A42B 3/121 with at least one layer or pad containing a fluid
• CPC Class Codes: A43B 1/0036 with fluorescent or phosphorescent parts
• CPC Class Codes: A43B 1/0054 provided with magnets, magnetic parts or magnetic substances
• CPC Class Codes: A43B 13/189 filled with a non-compressible fluid, e.g. gel, water
• CPC Class Codes: A43B 7/142 situated under the medial arch, i.e. under the navicular or cuneiform bones
• CPC Class Codes: A43B 7/144 situated under the heel, i.e. the calcaneus bone
• CPC Class Codes: A43B 7/18 Joint supports, e.g. instep supports
• CPC Class Codes: A43B 7/28 Adapting the inner sole or the side of the upper of the shoe to the sole of the foot
• CPC Class Codes: A61K 2800/54 Polymers characterized by specific structures/properties
• CPC Class Codes: A61K 47/34 Macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds, e.g. polyesters, polyamino acids, polysiloxanes, polyphosphazines, copolymers of polyalkylene glycol or poloxamers A61K47/10 takes precedence
• CPC Class Codes: A61K 8/042 Gels
• CPC Class Codes: A61K 8/91 Graft copolymers A61K8/89 takes precedence
• CPC Class Codes: A61Q 19/00 Preparations for care of the skin
• CPC Class Codes: A61Q 7/00 Preparations for affecting hair growth
• CPC Class Codes: A63B 71/081 fluid-filled, e.g. air-filled
• CPC Class Codes: A63B 71/143 Baseball or hockey gloves
• CPC Class Codes: B29D 35/126 Uppers

Abstract

A responsive polymer network exhibiting the property of reversible gelation in response to a change in an environmental stimulus is provided. The aqueous solution of the network polymer, comprises about 0.01 to 20 wt % by weight of a responsive component and about 0.01 to 20 wt % by weight of a structural component capable of supporting and interacting with the responsive component. The aqueous composition exhibits at least a five-fold increase in viscosity upon gelation. The gelation may be triggered by a change in an environmental stimulus, such as temperature, pH and ionic strength.

Claims

1. An responsive polymer network, comprising:

a responsive component capable of aggregation in response to a change in an environmental stimulus;

a structural component which supports and interacts with the responsive component; and

an aqueous-based solvent

wherein said responsive polymer network comprises less than about 4 weight percent of total polymer solids and further wherein the viscosity of the responsive polymer network increases by at least about 30 times or more upon exposure to the environmental stimulus and still further wherein the responsive and structural components interact with one another.

2. The responsive polymer network of claim 1, wherein said responsive component is an oligomer or polymer.

3. The responsive polymer network of claim 1, wherein said structural component is an oligomer or polymer.

4. The responsive polymer network of claim 1, wherein the aqueous-based solvent is selected from the group consisting of water, salt solutions and water with water-miscible organic compound(s).

5. The responsive polymer network of claim 1, wherein the responsive component comprises at least a hydrophobic component and a hydrophilic component.

6. The responsive polymer network of claim 1, wherein the responsive component comprises at least a hydrophobic component and a hydrophilic component.

7. The responsive polymer network of claim 1, wherein the responsive component is present in a range of about 1 to 10 wt % based on the weight of the total polymer solids and the structural component is present in a range of 99 to 90 wt % based on the weight of the total polymer solids.

8. The responsive polymer network of claim 1, wherein the responsive component is present in a range of about 11 to 20 wt % based on the weight of the total polymer solids and the structural component is present in a range of 89 to 80 wt % based on the weight of the total polymer solids.

9. The responsive polymer network of claim 1, wherein the responsive component is present in a range of about 21 to 30 wt % based on the weight of the total polymer solids and the structural component is present in a range of 79 to 70 wt % based on the weight of the total polymer solids.

10. The responsive polymer network of claim 1, wherein the responsive component is present in a range of about 31 to 40 wt % based on the weight of the total polymer solids and the structural component is present in a range of 69 to 60 wt % based on the weight of the total polymer solids.

11. The responsive polymer network of claim 1, wherein the responsive component is present in a range of about 41 to 50 wt % based on the weight of the total polymer solids and the structural component is present in a range of 59 to 50 wt % based on the weight of the total polymer solids.

12. The responsive polymer network of claim 1, wherein the responsive component is present in a range of about 51 to 60 wt % based on the weight of the total polymer solids and the structural component is present in a range of 49 to 40 wt % based on the weight of the total polymer solids.

13. The responsive polymer network of claim 1, wherein the responsive component is present in a range of about 61 to 70 wt % based on the weight of the total polvmer solids and the structural component is present in a range of 39 to 30 wt % based on the weight of the total polymer solids.

14. The responsive polymer network of claim 1, wherein the responsive component is present in a range of about 71 to 80 wt % based on the weight of the total polymer solids and the structural component is present in a range of 29 to 20 wt % based on the weight of the total polymer solids.

15. The responsive polymer network of claim 1, wherein the responsive component is present in a range of about 81 to 90 wt % based on the weight of the total polvmer solids and the structural component is present in a range of 19 to 10 wt % based on the weight of the total polymer solids.

16. The responsive polymer network of claim 1, wherein the responsive component is present in a range of about 91 to 99 wt % based on the weight of the total polymer solids and the structural component is present in a range of 9 to 1 wt % based on the weight of the total polymer solids.

17. The responsive polymer network of claim 1, wherein the structural component is branched.

18. The responsive polymer network of claim 1, wherein the structural component is prepared from a monomer selected from the group consisting of carboxylic acids, acrylic acid, substituted acrylic acid, methacrylic acid, substituted methacrylic acids, vinylcarboxylic acids, vinylsulfonic acids, substituted vinylsulfonic acids, vinylpyrolidone, vinylacetic acid, substituted vinylacetic acid, amines, acrylamides, substituted acrylamides, acrylate esters, substituted acrylate esters, methacrylate esters, substituted methacrylate esters, AMPS, MAPTEC, vinyl pyridine, urethanes, amino acids, thiopenes, nucleotides and ionized forms thereof.

19. The responsive polymer network of claim 1, wherein the structural component comprises polyacrylic acid or neutralized polyacrylic acid.

20. The responsive polymer network of claim 1, wherein the structural component comprises a copolymer.

21. The responsive polymer network of claim 1, wherein the structure component comprises a copolymer of acrylic acid and methacrylic acid.

22. The responsive polymer network of claim 1, wherein the branching structural component has a degree of branching greater than a=1.0, as determined by a Mark-Houwink plot.

23. The responsive polymer network of claim 1, wherein the responsive component comprises a polyoxyalkylene polymer.

24. The responsive polymer network of claim 23, wherein the polyoxyalkylene polymer comprises a block copolymer of different oxyalkylene groups, such that at least one polymer block possesses hydrophilic characteristics and at least one block possesses hydrophobic characteristics.

25. The responsive polymer network of claim 23, wherein the block copolymer comprise polyoxyethylene (POE) and polyoxypropylene (POP).

26. The responsive polymer network of claim 23, wherein the polyoxyalkylene polymer comprises a triblock polymer of polyoxyethylene (POE) and polyoxypropylene (POP) having the formula (POP)_a (POE)_b (POP)_c, where a is in the range of 10-50 and b is in the range of 50-70.

27. The responsive polymer network of claim 1, wherein the responsive component comprises a nonionic surfactant polymer.

28. The responsive polymer network of claim 1, wherein the responsive component comprises a poly(alkyl-co-oxyalkylene) having the formula R--(OCH₂ CH)_n --OH, where R is an alkyl group.

29. The responsive polymer network of claim 1, wherein the responsive component is selected from the group consisting of cellulosic, cellulose ethers and guar gums.

30. The responsive polymer network of claim 1, wherein the composition exhibits at least about a 10-fold increase in viscosity upon gelation over a temperature of less than 10°

C.

31. The responsive polymer network of claim 1, wherein the composition exhibits at least about a 30-fold increase in viscosity upon gelation over a temperature of less than 10°

C..

32. The responsive polymer network of claim 1, wherein the environmental stimulus for reversible gelation is selected from the group consisting of temperature, pH, ionic strength, light irradiation, electric field strength and solvent composition.

33. The responsive polymer network of claim 1, characterized in that the gel remains translucent to light before and after response to the environmental stimulus.