SELF-REPAIRING, REINFORCED MATRIX MATERIALS

• US 20060169180A1
• Filed: 04/04/2006
• Published: 08/03/2006
• Est. Priority Date: 06/19/1990
• Status: Abandoned Application

• Current Assignee: Carolyn M. Dry
• Original Assignee: Carolyn M. Dry
• Inventors: Dry, Carolyn M.
• Application Number:
  US11/278,631
• Publication Number:
  US 20060169180A1
• Time in Patent Office: Days
• US Class Current: 106/711
• CPC Class Codes: A61L 27/48 with macromolecular fillers
• CPC Class Codes: B28B 17/00 Details of, or accessories for, apparatus for shaping the material; Auxiliary measures taken in connection with such shaping moulds B28B7/00; after-treatment B28B11/00; feeding or discharging B28B13/00; arrangements for embedding elements in the material B28B23/00
• CPC Class Codes: B29C 73/163 Sealing compositions or agents, e.g. combined with propellant agents
• CPC Class Codes: B29C 73/22 the article containing elements including a sealing composition, e.g. powder being liberated when the article is damaged
• CPC Class Codes: B32B 15/14 next to a fibrous or filamentary layer
• CPC Class Codes: B32B 15/18 comprising iron or steel B32B15/011, B32B15/012 and B32B15/013 take precedence
• CPC Class Codes: B32B 15/20 comprising aluminium or copper B32B15/016 and B32B15/017 take precedence
• CPC Class Codes: B32B 17/04 bonded with or embedded in a plastic substance
• CPC Class Codes: B32B 17/10036 comprising two outer glass sheets
• CPC Class Codes: B32B 17/10963 specially adapted for repairing the layered products
• CPC Class Codes: B32B 2250/03 3 layers
• CPC Class Codes: B32B 2250/40 Symmetrical or sandwich layers, e.g. ABA, ABCBA, ABCCBA
• CPC Class Codes: B32B 2307/54 Yield strength; Tensile strength
• CPC Class Codes: B32B 2307/554 Wear resistance
• CPC Class Codes: B32B 2307/762 Self-repairing, self-healing
• CPC Class Codes: B32B 2603/00 Vanes, blades, propellers, rotors with blades
• CPC Class Codes: B32B 2605/18 Aircraft blades, propellers B32B2603/00
• CPC Class Codes: B32B 5/02 characterised by structural features of a fibrous or filamentary layer layer formed of metallic wires B32B15/02; layer formed of natural mineral fibres B32B19/02; layer formed of wood fibres B32B21/02
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: C04B 20/0048 Fibrous materials
• CPC Class Codes: C04B 20/0056 : Hollow or porous fibres
• CPC Class Codes: C04B 20/1025 : Fats; Fatty oils; Ester type waxes; Higher fatty acids; Derivatives thereof
• CPC Class Codes: C04B 2103/00 : Function or property of ingredients for mortars, concrete or artificial stone
• CPC Class Codes: C04B 2103/0046 : added as monomers or as oligomers
• CPC Class Codes: C04B 2103/0067 : the ingredients being formed in situ by chemical reactions or conversion of one or more of the compounds of the composition
• CPC Class Codes: C04B 2111/72 : Repairing or restoring existing buildings or building materials
• CPC Class Codes: C04B 22/006 : released by a chemical reaction, e.g. polymer condensation
• CPC Class Codes: C04B 22/085 : containing nitrogen in the anion, e.g. nitrites
• CPC Class Codes: C04B 2235/3217 : Aluminum oxide or oxide forming salts thereof, e.g. bauxite, alpha-alumina
• CPC Class Codes: C04B 2235/524 : Non-oxidic, e.g. borides, carbides, silicides or nitrides
• CPC Class Codes: C04B 2235/5284 : Hollow fibers, e.g. nanotubes
• CPC Class Codes: C04B 2235/80 : Phases present in the sintered or melt-cast ceramic products other than the main phase
• CPC Class Codes: C04B 24/08 : Fats; Fatty oils; Ester type waxes; Higher fatty acids, i.e. having at least seven carbon atoms in an unbroken chain bound to a carboxyl group; Oxidised oils or fats
• CPC Class Codes: C04B 24/282 : Polyurethanes; Polyisocyanates
• CPC Class Codes: C04B 24/32 : Polyethers, e.g. alkylphenol polyglycolether
• CPC Class Codes: C04B 24/42 : Organo-silicon compounds
• CPC Class Codes: C04B 26/02 : Macromolecular compounds
• CPC Class Codes: C04B 26/14 : Polyepoxides
• CPC Class Codes: C04B 28/02 : containing hydraulic cements other than calcium sulfates
• CPC Class Codes: C04B 28/34 : containing cold phosphate binders
• CPC Class Codes: C04B 35/52 : based on carbon, e.g. graphite
• CPC Class Codes: C04B 35/80 : Fibres, filaments, whiskers, platelets, or the like
• CPC Class Codes: C04B 38/0003 : containing continuous channels, e.g. of the "dead-end" type or obtained by pushing bars in the green ceramic product B28B takes precedence
• CPC Class Codes: C04B 40/0028 : Aspects relating to the mixing step of the mortar preparation
• CPC Class Codes: C04B 40/0092 : Temporary binders, mortars or concrete, i.e. materials intended to be destroyed or removed after hardening, e.g. by acid dissolution
• CPC Class Codes: C04B 40/0263 : Hardening promoted by a rise in temperature C04B40/024 takes precedence
• CPC Class Codes: C04B 40/06 : Inhibiting the setting, e.g. mortars of the deferred action type containing water in breakable containers ; Inhibiting the action of active ingredients
• CPC Class Codes: C04B 40/0633 : Chemical separation of ingredients, e.g. slowly soluble activator
• CPC Class Codes: C04B 40/0641 : Mechanical separation of ingredients, e.g. accelerator in breakable microcapsules
• CPC Class Codes: C04B 40/0675 : Mortars activated by rain, percolating or sucked-up water; Self-healing mortars or concrete
• CPC Class Codes: C08J 3/241 : Preventing premature crosslinking by physical separation of components, e.g. encapsulation
• CPC Class Codes: C08K 7/00 : Use of ingredients characterised by shape
• CPC Class Codes: C08K 7/02 : Fibres or whiskers
• CPC Class Codes: C22C 47/00 : Making alloys containing metallic or non-metallic fibres or filaments
• CPC Class Codes: C22C 47/04 : by coating, e.g. with a protective or activated covering
• CPC Class Codes: C22C 49/00 : Alloys containing metallic or non-metallic fibres or filaments
• CPC Class Codes: C22C 49/14 : characterised by the fibres or filaments
• CPC Class Codes: Y10T 428/249971 : Preformed hollow element-containing
• CPC Class Codes: Y10T 428/249994 : Composite having a component wherein a constituent is liquid or is contained within preformed walls [e.g., impregnant-filled, previously void containing component, etc.]
• CPC Class Codes: Y10T 428/249995 : Constituent is in liquid form
• CPC Class Codes: Y10T 428/249997 : Encapsulated liquid

Abstract

Self-repairing, fiber reinforced matrix materials include a matrix material including inorganic as well as organic matrices. Disposed within the matrix are hollow fibers having a selectively releasable modifying agent contained therein. The hollow fibers may be inorganic or organic and of any desired length, wall thickness or cross-sectional configuration. The modifying agent is selected from materials capable of beneficially modifying the matrix fiber composite after curing. The modifying agents are selectively released into the surrounding matrix in use in response to a predetermined stimulus be it internal or externally applied. The hollow fibers may be closed off or even coated to provide a way to keep the modifying agent in the fibers until the appropriate time for selective release occurs. Self-repair, smart fiber matrix composite materials capable of repairing microcracks, releasing corrosion inhibitors or permeability modifiers are described as preferred embodiments in concrete and polymer based shaped articles.

Claims

1. A structure comprising:

a matrix comprising an interconnected continuous structure of a plurality of hollow fibers having a length of less than about 1 inch, the fibers comprising modifying agent that is contained until released to flow into the matrix in response to an external stimulus.

2. The structure of claim 1 wherein the matrix comprises a three-dimensional shape.

3. The structure of claim 1 wherein the external stimulus is heating, cooling, loading, impacting, cracking, water infusion, chloride infusion, alkalinity changes, acidity changes, acoustic excitation, low frequency wave excitations, hydrostatic pressure, rolling pressure, light sensitivity or laser excitation, electric current, voltage, electrorheological excitation, or radiation.

4. The structure of claim 1 wherein the hollow fibers comprise fiberglass, cement, asphalt, hydroxyapatite, glass, ceramic, metal, polyolefin, polyester, polycarbonate, polyacrylate, polyarylate, polyamide, polyimide, polyaramide, polyurethane, carbon, graphite, cellulose, nitrocellulose, hydrocarbon, or piezoelectric material.

5. The structure of claim 1 wherein the hollow fibers have at least one end open to the outside.

6. The structure of claim 1 wherein the hollow fibers have at least one open end.

7. The structure of claim 1 wherein the hollow fibers comprise a coating which will selectively degrade upon the occurrence of a particular external stimulus.

8. The structure of claim 7 wherein the coating is a heat sensitive coating, a pH sensitive coating, or an ion sensitive coating.

9. The structure of claim 8 wherein the coating is a wax, low molecular weight hydrocarbon oil, or coating polymer.

10. The structure of claim 7 wherein the particular external stimulus is heating, cooling, loading, impacting, cracking, water infusion, chloride infusion, alkalinity changes, acidity changes, acoustic excitation, low frequency wave excitations, hydrostatic pressure, rolling pressure, light sensitivity or laser excitation, electric current, voltage, electrorheological excitation, or radiation.

11. The structure of claim 1 wherein the modifying agent of the fiber is a fluid.

12. The structure of claim 1 wherein the modifying agent is methyl methacrylate, styrene, or epoxy.

13. The structure of claim 1, wherein the matrix comprises a ceramic, metal, cementitious or polymer matrix.

14. The structure of claim 13, wherein the matrix material comprises metal and the metal is any of aluminum, iron, lead, copper, steel, bronze, phosphor bronze, and brass.

15. The structure of claim 13, wherein the matrix comprises a cementitious material and further comprises a reinforcement.

16. The structure of claim 1, wherein the matrix comprises a biomimetic system.

17. The structure of claim 16, wherein the biomimetic system comprises organic or inorganic materials.

18. The structure of claim 1, wherein the structure is a biomedical device.

19. The structure of claim 1, wherein the structure is an aircraft structure, a space vehicle or a satellite.

20. The structure of claim 1, wherein the structure is a bridge or a building.

21. The structure of claim 1, wherein the structure is a helicopter blade.

22. The structure of claim 1, wherein the structure is a sandwich panel.

23. A structure comprising:

a matrix comprising an interconnected continuous structure of a plurality of porous walled, hollow fibers comprising a repair chemical that is contained until released to flow into the matrix.

24. The structure of claim 23 wherein the hollow fibers have a length of less than about 1 inch.

25. The structure of claim 24, wherein the hollow fibers have a diameter of less than 100 microns.

26. The structure of claim 23 wherein the repair chemical of the fiber is a fluid.

27. The structure of claim 23 wherein the hollow fibers comprise fiberglass, cement, asphalt, hydroxyapatite, glass, ceramic, metal, polyolefin, polyester, polycarbonate, polyacrylate, polyarylate, polyamide, polyimide, polyaramide, polyurethane, carbon, graphite, cellulose, nitrocellulose, hydrocarbon, or piezoelectric material.

28. The structure of claim 27, wherein the hollow fiber comprises metal and are conductive.

29. A method of repairing a microcrack in a shaped article, the shaped article comprising a matrix, comprising:

providing the matrix comprising a plurality of fibers and a repair chemical; and

releasing the repair chemical from the fibers into the matrix upon an external stimulus.

30. The method of claim 29, further comprising rebonding the fibers to the matrix.

31. The method of claim 30, further comprising repairing the fibers themselves.

32. The method of claim 29, wherein the fibers are twisted.

33. The method of claim 29, wherein the repair chemical comprises two part epoxies, wherein an epoxy precursor material is disposed in a first fiber and a cross-linking agent is disposed in an adjacent second fiber.

34. The method of claim 29, wherein the fiber comprises an external coating, and wherein the method comprises selectively degrading the external upon the occurrence of the external stimulus.

35. The method of claim 34, wherein the external coating comprises wax and the external stimulus comprises heat.

36. A shaped article of composite material comprising a cured matrix, at least one hollow release vessel, and a modifying agent, wherein the modifying agent is capable of beneficially modifying the composite material in response to a predetermined external stimulus.

37. The article of claim 36 wherein the modifying agent is selected from the group consisting of polyolefin, polyester, polyamide, polyaramid, polyimide, carbon, graphite, cellulose, nitrocellulose, hydrocarbons, polytetrafluoroethylene, aramids, polypropylene, and elastomers.

38. A method for making an in situ composite comprising the steps of:

selecting a first reactive chemical;

dispensing the first reactive chemical into a mold containing at least one second reactive chemical, composite fibers, and an activator located in fibers.

39. The method of claim 38 wherein the first reactive chemical and the at least one second reactive chemical bond the fibers to each other.

40. The method of claim 38 wherein the mold contains a modifying chemical comprising a solvent.

41. The method of claim 38 wherein the composite is selected from the group consisting of a wrap, a web or a fabric.

42. The method of claim 38 wherein the fibers include a coating that acts as a modifying agent.

43. The method of claim 38 wherein the fibers comprise a modifying agent.