Abstract: The present invention relates to a method for the formation of amorphous boron silicon oxycarbide fibers and crystalline boron-doped silicon carbide fibers wherein the method comprises preparing a blend of a siloxane resin and a carborane-siloxane oligomer, forming the blend into green fibers, and then curing and pyrolyzing the fibers.

Abstract: The present invention relates to a method for the formation of amorphous boron silicon oxycarbide fibers and crystalline boron-doped silicon carbide fibers comprising: preparing a blend of a siloxane resin and a boron-containing polymer, forming the blend into green fibers, and then curing and pyrolyzing the fibers.

Abstract: This invention relates to the preparation of thermally stable, substantially polycrystalline silicon carbide ceramic fibers using borosilazane resins. The method comprises spinning fibers from the resin, infusibilizing the spun fibers and pyrolyzing the spun fibers at a temperature greater than about 1700.degree. C.

Abstract: The present invention relates to a method for preparing a ceramic fiber from alkenyl or alkynyl functional resins and to the ceramic fibers produced therefrom. The method comprises (A) forming a fiber from a siloxane resin comprised of R.sup.1.sub.a R.sup.2.sub.b RSiO.sub.(3-a-b)/2 units wherein R is an unsaturated carbon group; each R.sup.1 is selected from the group consisting essentially of an aryl group having from 6 to 10 carbon atoms and functional derivatives thereof; each R.sup.2 is selected from the group consisting essentially of an alkyl group having from 1 to 4 carbon atoms and functional derivatives thereof; a has a value of 0, 1 or 2; b has a value of 0, 1, or 2 with the proviso that a+b <2; (B) curing the fiber by exposing the fiber to high energy radiation to render it non-fusible; and (C) heating the non-fusible fiber in an inert environment to a temperature above about 800.degree. C. to convert it to a ceramic fiber.

Abstract: The present invention relates to a method for preparing a ceramic fiber wherein the method comprises (A) forming a green fiber from an alk-1-enyl ether functional siloxane resin of the general formula (R.sup.1 SiO.sub.3/2).sub.q (R.sup.2 SiO.sub.3/2).sub.r (R.sup.1.sub.w R.sup.2.sub.x RSiO.sub.(3-w-x)/2).sub.s (R.sup.1.sub.w R.sup.2.sub.x R.sup.3 SiO.sub.(3-w-x)/2).sub.t wherein R is an alk-1-enyl ether group; each R.sup.1 is selected from an aryl group having from 6 to 10 carbon atoms; each R.sup.2 is selected from an alkyl group having from 1 to 4 carbon atoms; R.sup.3 is an alkenyl group having from 2 to 10 carbon atoms; w has a value of 0, 1 or 2; x has a value of 0, 1, or 2 with the provisio that w+x.ltoreq.2; q has a value of 0 to 0.98; r has a value of 0 to 0.98; s is greater than zero; t.gtoreq.0; s+t=0.02 to 0.5 and q+r+s+t=1; (B) curing the green fiber to render it non-fusible; and (C) heating the non-fusible fiber in an inert environment to a temperature above 800.degree. C.

Abstract: A method of crosslinking a silazane polymer having Si--H bonds in which the polymer is mixed with a crosslinker selected from alkenyl functional cyclosiloxanes and alkenyl functional cyclosilazanes and a crosslinking promoter and then heated to a temperature sufficient to crosslink the silazane polymer. The mixture of the silazane polymer, crosslinker and promoter is useful in the formation of ceramic matrix composites.

Abstract: A method of crosslinking a silazane polymer having Si--H bonds in which the polymer is mixed with a crosslinker selected from alkenyl functional cyclosiloxanes and alkenyl functional cyclosilazanes and a crosslinking promoter and then heated to a temperature sufficient to crosslink the silazane polymer. The mixture of the silazane polymer, crosslinker and promoter is useful in the formation of ceramic matrix composites.