초록 ▼

Hollow ceramic fibers are prepared by melt spinning an organic silazane polymer, infusibilizing the fiber to form an infusible layer on the surface, and pyrolyzing the fiber to obtain a ceramic fiber having an empty interior. The infusibilizing step includes two steps of treating the fiber with a ga

Hollow ceramic fibers are prepared by melt spinning an organic silazane polymer, infusibilizing the fiber to form an infusible layer on the surface, and pyrolyzing the fiber to obtain a ceramic fiber having an empty interior. The infusibilizing step includes two steps of treating the fiber with a gas containing the vapor of an infusibilizing silicon, boron, phosphorus or metal compound and further treating with a water vapor-containing gas or ammonia-containing gas. The surface infusible fibers are efficiently sintered into hollow ceramic fibers without fusion bond.

대표청구항 ▼

A method for preparing a hollow ceramic fiber, comprising the steps of: (A) melt spinning an organic silazane polymer into a fiber, (B) treating the surface of the fiber with a gas containing the vapor of at least one compound selected from the group consisting of silicon compounds of formula (1): R

A method for preparing a hollow ceramic fiber, comprising the steps of: (A) melt spinning an organic silazane polymer into a fiber, (B) treating the surface of the fiber with a gas containing the vapor of at least one compound selected from the group consisting of silicon compounds of formula (1): RaSiX4-a (1) wherein R is a radical selected from the group consisting of hydrogen, lower alkyl, alkenyl, and aryl radicals, X is a chlorine, bromine or iodine atom, and letter a has a value of from 0 to 2, R radicals may be the same or different when a is equal to 2; boron compounds of formula (2): BX3 (2) wherein X is as defined above; phosphorus compounds of formula (3): PXb (3) wherein X is as defined above, and letter b is equal to 3 or 5; and metal compounds of formula (4): MXc (4) wherein M is a metal selected from the group consisting of Al, Ti, V, Fe, Ga, Ge, Zr, Nb, Sn, Sb, Te, Ta, W, and Bi, letter c is a number equal to the valence of the metal, and X is as defined above, (C) subjecting the fiber to hydrolysis with a water vapor-containing gas or ammonolysis with ammonia-containing gas, thereby forming an infusible layer on the fiber surface, and (D) subjecting the fiber to pyrolysis to form a hollow ceramic fiber having an empty interior.