Boron nitride fiber and process for production thereof
US5780154A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 22, 1995 |
| Grant date | Jul 14, 1998 |
| Priority date | — |
| Expiry date | Nov 22, 2015 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/2916
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A boron nitride fiber comprising hexagonal and/or turbostratic boron nitride having C planes oriented substantially parallel to the fiber axis and a degree of orientation of 0.74 or above can be obtained by heating an adduct between a boron trihalide such as boron trichloride or the like and a nitrile compound such as acetonitrile, benzonitrile or the like, and an ammonium halide or a primary amine hydrohalide in the presence of a boron trihalide at around 125.degree. C. to form a boron nitride precursor, dissolving the boron nitride precursor in a solvent such as N,N'-dimethyl formamide or the like, capable of dissolving the precursor, spinning the solution to obtain a boron nitride precursor fiber, heat-treating the precursor fiber in an inert gas atmosphere and then in an ammonia gas atmosphere to obtain a boron nitride fiber, and heat-treating the boron nitride fiber with a tensile stress being applied to the fiber. The boron nitride fiber of the present invention has a degree of orientation of 0.74 or above and therefore has a high tensile strength.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.