Claims
- 1. An oxidized stabilized nonmesophase pitch fiber having a diameter in the range of about 5 to 50 microns diameter, having a percent elongation to break of at least about 2 percent and sufficient to enable machine handling in an elastic range with no plastic range, said fiber also having a tensile strength of at least about 10,000 psi, a Young's modulus of at least about 0.4.times.10.sup.6 psi and a surface area as low as 100 m.sup.2 /gm and up to about 600 m.sup.2 /gm.
- 2. The fiber of claim 1 wherein the fiber is impervious to most chemicals and is heat resistant when subjected to exposure of temperatures up to about 2500.degree. C.
- 3. The fiber of claim 1 wherein the fiber has a diameter in the range of about 5 to about 15 microns.
- 4. The fiber of claim 1 wherein the electrical resistance is about 10.sup.-2 ohm-cm.
- 5. The fiber of claim 1 having a percent elongation at break in the range of about 5% to about 8%.
- 6. The fiber of claim 1 prepared by oxidizing a pitch fiber having essentially no mesophase content to an oxidation extent and subsequently heat treating in an inert atmosphere to a heat treatment temperature of at least about 420.degree. C.
- 7. A fiber as in claim 6 having a diameter of from about 5 to about 15 microns.
- 8. A fiber as in claim 6 having electrical resistivity of about 10.sup.-2 ohm-cm.
- 9. A fiber as in claim 6 having elongation of about 8%.
- 10. A fiber as in claim 6 wherein said heat treatment temperature is between about 500.degree. C. and 520.degree. C.
- 11. The fiber of claim 6 wherein said fiber is heat resistant when subjected to exposures of temperatures up to about 2,500.degree. C.
- 12. The fiber of claim 1 wherein said fiber is electrically non-conductive.
- 13. The fiber of claim 1 wherein the fiber is an elongate isotropic fiber.
- 14. The fiber of claim 6 wherein said fiber is electrically non-conductive.
- 15. An oxidized stabilized nonmesophase pitch fiber, comprising an elongate isotropic fiber having a surface area as low as 100 m.sup.2 /gm and up to about 600 m.sup.2 /gm, having a percent elongation at break of at least about 2 percent and sufficient to enable machine handling, having a diameter of about 5 to about 50 microns, having a tensile strength within the range from about 10,000 psi up to about 22,000 psi and having a Young's modulus of at least about 0.4.times.10.sup.6 psi.
- 16. The fiber of claim 6 wherein said fiber has a tensile strength up to about 22,000 psi.
- 17. The fiber of claim 6 wherein said heat treatment temperature is within the range of from at least about 420.degree. C. to about 520.degree. C.
Parent Case Info
This disclosure is a continuation in part of application Ser. No. 700,231 filed Feb, 11, 1985, now abandoned, and also of application Ser. No. 944,479 filed Dec. 22, 1986, and also is a division of application Ser. No. 907,931 filed Sept. 16, 1986. All the cited applications are assigned to a common assignee and are incorporated by reference.
US Referenced Citations (4)
Number |
Name |
Date |
Kind |
4497789 |
Sawran et al. |
Feb 1985 |
|
4554148 |
Gomi et al. |
Nov 1985 |
|
4591424 |
Gomi et al. |
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Divisions (1)
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Number |
Date |
Country |
Parent |
907931 |
Sep 1986 |
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