| 摘要 |
<p>A boron nitride fiber comprising hexagonal and/or turbostratic boron nitride and having a C plane oriented in parallel with the fiber axis and a degree of crystal orientation of 0.74 or above. It is produced by preparing a boron nitride precursor by heating an adduct formed between a boron trihalide, such as boron trichloride, and a nitrile compound, such as acetonitrile or benzonitrile, and an ammonium halide or a primary amine hydrohalide in the presence of a boron trihalide at around 125 DEG C, dissolving the obtained precursor in a solvent which can dissolve the same, spinning a boron nitride precursor fiber from the obtained solution, heat treating the spun precursor fiber in an inert gas atmosphere and then in an ammonia gas atmosphere to prepare a boron nitride fiber, and heat treating the obtained fiber while applying a tensile stress to the fiber. The obtained fiber, having a degree of crystal orientation of 0.74 or above, exhibits a high tensile strength.</p> |
