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Effects of sequential treatment with fluorine and bromine on graphite fibers
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Stahl, Mark Slabe, Melissa Maciag, Carolyn Hung, Ching-Cheh |
| Copyright Year | 1987 |
| Description | Three pitch based graphite fibers with different degrees of graphitization and one polyacryonitrile (PAN) based carbon fiber from Amoco Corporation were treated with 1 atm, room temperature fluorine gas for 90 hrs. Fluorination resulted in higher electrical conductivity for all pitch fibers. Further bromination after ambient condition defluorination resulted in further increases in electrical defluorination conductivity for less graphitized, less structurally ordered pitch fibers (P-55) which contain about 3% fluorine by weight before bromination. This product can be stable in 200 C air, or 100% humidity at 60 C. Due to its low cost, this less graphitized fiber may be useful for industrial application, such as airfoil deicer materials. The same bromination process, however, resulted in conductivity decreases for fluorine rich, more graphitized, structurally oriented pitch fibers (P-100 and P-75). Such decreases in electrical conductivity were partially reversed by heating the fibers at 185 C in air. Differential scanning calorimetric (DSC) data indicated that the more graphitized fibers (P-100) contained BrF3, whereas the less graphitized fibers (P-55) did not. |
| File Size | 594433 |
| Page Count | 15 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19870015141 |
| Archival Resource Key | ark:/13960/t3sv2gg82 |
| Language | English |
| Publisher Date | 1987-07-01 |
| Access Restriction | Open |
| Subject Keyword | Nonmetallic Materials Heat Treatment Electrical Resistivity Bromination Calorimeters Temperature Effects Nitriles Chemical Composition Fluorination Fibers Graphitization Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Technical Report |
