초록 ▼

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 nitri

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.

대표청구항 ▼

[ We claim:] [1.] A boron nitride fiber comprising boron nitride having a multi-layered structure consisting of planes (C planes) each formed by linkage of 6-membered rings in the plane, in which boron and nitrogen are positioned alternately and bonded to each other, which fiber has a tensile streng

[ We claim:] [1.] A boron nitride fiber comprising boron nitride having a multi-layered structure consisting of planes (C planes) each formed by linkage of 6-membered rings in the plane, in which boron and nitrogen are positioned alternately and bonded to each other, which fiber has a tensile strength of at least 1,400 MPa.