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US4351878A
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US
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Coating for gasifiable carbon-graphite fibers
Assignee: National Aeronautics and Space Administration
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Filing: 1980-06-30
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Granted: 1982-09-28
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Expires: 2000-06-30
Abstract
Abstract A thin, uniform, firmly adherent coating of metal gasification catalyst is applied to a carbon-graphite fiber by first coating the fiber with a film-forming polymer containing functional moieties capable of reaction with the catalytic metal ions. Multivalent metal cations such as calcium cross-link the polymer such as a polyacrylic acid to insolubilize the film by forming catalytic metal macro-salt links between adjacent polymer chains. The coated fibers are used as reinforcement for resin composites and will gasify upon combustion without evolving conductive airborne fragments.
Inventors
- 👤 Jan Harper-Tervet
- 👤 Warren L. Dowler
- 👤 Shiao-Ping S. Yen
- 👤 William A. Mueller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 05:54
CPC Classifications
C; C04; C04B; C04B41/00; C04B41/80; C04B41/81; C04B41/89; C04B20/00; C04B20/10; C04B20/1018; C04B20/1029; C04B20/1033; C04B26/00; C04B26/02; C04B26/10; C04B41/009; C04B41/45; C04B41/4584; C04B41/52; C08; C08J; C08J5/00; C08J5/04; C08J5/0405; C08J5/042; C08J5/06; D; D01; D01F; D01F11/00; D01F11/10; D01F11/14; D06; D06M; D06M17/00; D06M17/04; Y; Y10; Y10S; Y10S428/00; Y10S428/902; Y10S428/903; Y10T; Y10T428/00; Y10T428/29; Y10T428/2913; Y10T428/2918; Y10T428/2933; Y10T428/2964
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
105 words
A composition of matter comprising: graphite fibers having a diameter from 1 to 30 microns directly coated with 0.1 to 10% by weight of a thin, uniform, firmly adherent, film of a linear organic polymer containing anion groups selected from sulfonic, carboxyl or phosphonic which are cross-linked by cations of a polyvalent metal having a work function below 4.2 eV to form macrosalt cross-links with said groups on adjacent polymer chains; said metal being present in an amount of 0.05 to 20% by weight; and said coated fibers being dispersed and embedded in a binder resin in an amount of 30 to 70% by weight.
Claim 2
Dependent Claim
105 words
A composition of matter comprising: graphite fibers having a diameter from 1 to 30 microns directly coated with 0.1 to 10% by weight of a thin, uniform, firmly adherent, film of a linear organic polymer containing anion groups selected from sulfonic, carboxyl or phosphonic which are cross-linked by cations of a polyvalent metal having a work function below 4.2 eV to form macrosalt cross-links with said groups on adjacent polymer chains; said metal being present in an amount of 0.05 to 20% by weight; and said coated fibers being dispersed and embedded in a binder resin in an amount of 30 to 70% by weight.
Claim 3
Dependent Claim
18 words
A composition according to claim 1 in which the fibers are in the form of a multifilament yarn.
Claim 4
Dependent Claim
23 words
A composition according to claim 1 in which the binder resin is selected from epoxy, polyester, phenolic, silicone, polyimide, triazine or phthalocyanine resins.
Claim 5
Dependent Claim
13 words
A composition according to claim 3 in which the resin is an epoxy.
Claim 6
Dependent Claim
24 words
A composition according to claim 3 in which the coating material is a poly-acrylic acid and the cross-linking metal is an alkaline earth metal.
Claim 7
Dependent Claim
21 words
A composition according to claim 3 in which the coating material is a polyacrylic acid containing both divalent and monovalent cations.
Claim 8
Dependent Claim
18 words
A composition according to claim 6 in which the divalent metal is selected from calcium, barium and strontium.
Claim 9
Dependent Claim
19 words
A composition according to claim 7 in which the divalent metal is calcium and the monovalent metal is lithium.
Claim 10
Dependent Claim
22 words
A composition according to claim 1 further including 0.1 to 10% by weight of the metal cation dispersed in the binder resin.
Claim 11
Independent Claim
112 words
A method of forming a gasifiable fiber comprising the steps of: applying a 0.1 to 10% by weight of a thin, uniform, firmly adherent layer of a linear, organic polymer containing anion groups capable of cross-linking with multivalent metal cations selected from carboxyl, sulfonic and phosphonic directly to the exterior surface of a fine graphite fiber having a diameter from 1.0 to 30 microns; and applying a solution containing cations of a polyvalent metal gasification catalyst having a work function below 4.2 eV and reacting the metal cations with said anion groups on adjacent polymer chains to form macrosalt cross-links which insolubilize said layer to form an insoluble coating on the fiber.
Claim 12
Independent Claim
112 words
A method of forming a gasifiable fiber comprising the steps of: applying a 0.1 to 10% by weight of a thin, uniform, firmly adherent layer of a linear, organic polymer containing anion groups capable of cross-linking with multivalent metal cations selected from carboxyl, sulfonic and phosphonic directly to the exterior surface of a fine graphite fiber having a diameter from 1.0 to 30 microns; and applying a solution containing cations of a polyvalent metal gasification catalyst having a work function below 4.2 eV and reacting the metal cations with said anion groups on adjacent polymer chains to form macrosalt cross-links which insolubilize said layer to form an insoluble coating on the fiber.
Claim 13
Dependent Claim
53 words
A method according to claim 10 in which the polymer is applied to the fiber from a solution and further including the steps of drying the solution to form a polymer layer followed by reacting the polymer layer with said metal to crosslink said polymer to form an insoluble coating on the fiber.
Claim 14
Dependent Claim
27 words
A method according to claim 11 further including the step of dispersing the coated fibers in a binder resin and curing the resin to form a composite.
Claim 15
Dependent Claim
19 words
A method according to claim 11 in which the polymer is a polyacrylic acid and the metal is calcium.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-09-27 | 1986-03-29 | 1986-09-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-09-27 | 1990-03-29 | 1990-09-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-09-27 | 1994-03-29 | 1994-09-28 | $7700.00 | Window Closed / Lapsed |