High-strength carbonaceous fiber
US4671950A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 14, 1985 |
| Grant date | Jun 9, 1987 |
| Priority date | — |
| Expiry date | Nov 14, 2005 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD01F9/32
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A carbonaceous fiber having a carbon content of from 70 to 90%, a high tensile strength and a high modulus of elasticity, which is produced by a method which comprises preoxidizing an acrylic fiber in an oxidizing atmosphere at a temperature of from 10.degree. to 60.degree. C. below the decomposition point of said fiber, to prepare a preoxidized fiber having a degree of orientation of not less than 78% at an angle of X-ray diffraction (2.theta.) of 25.degree. and a specific gravity of from 1.30 to 1.40, pyrolyzing the preoxidized fiber in an inert gas atmosphere by passing the fiber firstly through a lower temperature zone having a temperature of not higher than 750.degree. C. and then through a higher temperature zone having a temperature of from 750.degree. to 950.degree. C., during the pyrolysis controlling the tension of the fiber so that the change of the fiber length during pyrolyzing is from +16% to -8.8% based on the length of the preoxidized fiber.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.