Pitch-based carbon fibers and pitch compositions and precursor fibers therefor
US4590055A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 23, 1983 |
| Grant date | May 20, 1986 |
| Priority date | — |
| Expiry date | Aug 23, 2003 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC10C3/00
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
The invention provides carbon fibers having mechanical properties equival to or even better than those of the polyacrylonitrile-based carbon fibers from a bituminous material, e.g. coal tar pitch, as the starting material. The starting pitch is first partially hydrogenated in tetrahydroquinoline under specific conditions followed by a heat treatment to give a pitch composition suitable for spinning which can be characterized by several parameters including the proportions of the carbons and hydrogens having different chemical shifts in the NMR analysis. The pitch composition for spinning is then subjected to spinning under specific conditions including the temperature condition for controlling the viscosity behavior of the molten pitch composition determined by use of the Andrade's equation and the pitch filament is then infusibilized in an oxidative atmosphere and carbonized in an inert atmosphere into carbon fibers having a tensile strength of at least 200 kg/mm.sup.2 and a tensile modulus of at least 10 tons/mm.sup.2.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.