Inorganic matrix compositions, composites and process of making the same

• US 6,899,837 B2
• Filed: 07/21/2004
• Issued: 05/31/2005
• Est. Priority Date: 09/20/2000
• Status: Expired due to Fees

• Current Assignee: Goodrich Corporation (Raytheon Technologies Corporation d/b/a RTX)
• Original Assignee: Goodrich Corporation (Raytheon Technologies Corporation d/b/a RTX)
• Inventors: Mazany, Anthony M., Robinson, John W., Cartwright, Craig L.
• Primary Examiner(s): Marcantoni, Paul
• Application Number:
  US10/897,293
• Publication Number:
  US 20050003214A1
• Time in Patent Office: 314 Days
• Field of Search: 264/101, 264/234, 264/333, 264/621, 264/640, 264/641, 264/642
• US Class Current: 264/101
• CPC Class Codes: C04B 14/10 Clay sepiolite C04B14/042; grog C04B18/025
• CPC Class Codes: C04B 14/386 Carbon carbon nanotubes C04B14/026
• CPC Class Codes: C04B 14/42 Glass
• CPC Class Codes: C04B 14/4693 Silicon carbide
• CPC Class Codes: C04B 20/0048 Fibrous materials
• CPC Class Codes: C04B 2103/002 Compounds of elements having a valency of 2
• CPC Class Codes: C04B 22/0013 Boron compounds
• CPC Class Codes: C04B 22/082 Acids
• CPC Class Codes: C04B 22/085 containing nitrogen in the anion, e.g. nitrites
• CPC Class Codes: C04B 22/124 Chlorides of ammonium or of the alkali or alkaline earth metals, e.g. calcium chloride
• CPC Class Codes: C04B 22/141 Acids
• CPC Class Codes: C04B 22/142 Sulfates
• CPC Class Codes: C04B 22/16 containing phosphorus in the anion, e.g. phosphates
• CPC Class Codes: C04B 28/006 containing mineral polymers, e.g. geopolymers of the Davidovits type
• CPC Class Codes: C04B 28/26 Silicates of the alkali metals
• CPC Class Codes: C04B 40/0259 Hardening promoted by a rise in pressure C04B40/024 takes precedence
• CPC Class Codes: C04B 40/0263 Hardening promoted by a rise in temperature C04B40/024 takes precedence
• CPC Class Codes: Y02P 40/10 Production of cement, e.g. improving or optimising the production methods; Cement grinding
• CPC Class Codes: Y10T 428/249928 Fiber embedded in a ceramic, glass, or carbon matrix
• CPC Class Codes: Y10T 428/25 Web or sheet containing structurally defined element or component and including a second component containing structurally defined particles
• CPC Class Codes: Y10T 428/252 : Glass or ceramic [i.e., fired or glazed clay, cement, etc.] [porcelain, quartz, etc.]

Abstract

A modified alkali silicate composition for forming an inorganic network. The modified alkali silicate matrix is made by reacting an alkali silicate (or its precursors such as an alkali hydroxide, a SiO₂ source and water), an acidic oxoanionic compound such as phosphoric acid, water and optionally one or more multivalent cation(s) selected from Groups 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 or 16 of the periodic table such as an alkaline earth salt, water and optional processing aids. An inorganic matrix composite can be prepared by applying a slurry of the modified aqueous alkali silicate composition to a reinforcing medium and curing the composite at a temperature from about 15° C. up to 1000° C. and a pressure of up to 20,000 psi for typical high-performance organic polymer processing (temperatures about 15° C. to about 200° C. and pressures <200 psi). The composite can be shaped by compression molding as well as other known fabrication methods.

Claims

1. A method of making an inorganic silicate composite comprising the steps of:

applying an aqueous slurry of a mixture of an alkali silicate, an oxoanionic compound, a clay filler, an alkaline earth salt and water to a reinforcing medium and curing the composite by applying heat at a temperature of about 15°

C. up to about 1000°

C.+, an external pressure from ambient to about 20,000 psi, and optionally under a vacuum of about ambient to about 10<sup>−

3</sup> torr.

2. The method of claim 1, wherein the composite is cured at a temperature of about 15°

C. up to about 200°

C. and an external pressure from ambient to about 200 psi, and optionally under a vacuum of about ambient to about 10<sup>−

3</sup> torr.

3. The method of claim 1, wherein the uncured composite is in form of bulk molding compound, sheet molding compound, powder and reinforcement, liquid and reinforcement, or prepreg.

4. The method of claim 1, wherein the composite is cured using processes which include compression molding, pultrusion, wet lay-up, filament winding, autoclave vacuum bag processing, non-autoclave vacuum bag processing, vacuum infusion, liquid resin, film infusion or powder infusion, resin transfer molding, extrusion, injection molding, casting, spin casting, or trapped elastomer molding.

5. The method of claim 1, wherein the composite is consolidated before and/or during the curing process.

6. The method of claim 1, wherein the slurry includes additional filler materials of carbon fibers, glass fibers, alkali resistant fibers, mineral fibers, organic fibers, ceramic fibers or metallic fibers, or combinations thereof.

7. The method of claim 1, wherein the slurry includes additional filler materials of graphite fibers, E-glass fibers, S-glass fibers, stainless steel fibers, titanium fibers, nickel alloy fibers, aramid fibers, polyethylene fibers, basalt fibers, SiC fibers or BN fibers, or combinations thereof.

8. The method of claim 1, wherein the reinforcing medium is a glass fiber such as an E-glass fiber, S-glass fiber and/or an alkaline resistant fiber.

9. The method of claim 1, wherein the slurry further includes a surface-active agent.

10. The method of claim 1, wherein the slurry further includes an anionic, cationic or a nonionic surface-active agent, or combinations thereof.

11. The method of claim 1, wherein the slurry further includes a surface-active agent of an alkylaryl sulfonate, silicone, quaternary ammonium salt, protonated organoamine salt, or combinations thereof.

12. The method of claim 1, wherein the slurry further includes a surface-active agent in an amount from none to about 10 wt. % based upon the weight of the total composition.

13. The method of claim 1, wherein the slurry further includes a surface-active agent in an amount from 0.5 wt. % to about 5 wt. % based upon the weight of the total composition.

14. The method of claim 1, wherein said oxoanionic compound is phosphoric acid or a salt of phosphoric acid.

15. The method of claim 1, wherein the slurry includes filler materials comprising ceramic powder, mineral powder, silicon carbide, silicon nitride, silicate, aluminum silicate, sodium aluminum silicate, potassium aluminum silicate, carbon, carbon black, molybdenum, or a molybdenum containing compound.

16. A method of making an inorganic silicate composite comprising the steps of:

applying an aqueous slurry of a mixture of an alkali silicate, phosphoric acid, water and optionally a clay filler, an alkaline earth salt and/or a gel modifier to a reinforcing medium and curing the composite by applying heat at a temperature of about 15°

C. up to about 1000°

C. and external pressures from ambient pressure to about 20,000 psi and/or under a vacuum of from about ambient to about 10<sup>−

3</sup> torr.