Abstract: Provided herein is a composition comprising from 50% to 60% polysiloxane consisting essentially of polyphenylmethylsiloxane and ?,?-methoxy-terminated polydimethylsiloxane, from 40% to 50% organic solvent, from 2% to 4% polysilazane, and polysilane of a formula (R1R2Si)n, wherein n is greater than 1, and wherein R1 and R2 are the same or different and are alkyl, alkenyl, cycloalkyl, alkylamino, aryl, aralkyl, or alkylsilyl. The composition, after curing, is a flame resistant binder for forming a composition-fiber composite that withstands repeated temperatures over 1800° F. The composition may further comprise from 0.1% to 2% of an enhancer selected from butyltitanate and aminoethylaminopropyltrimethoxysilane (H2NC2H4NHC3H6—Si(OCH3)3). The composition may be mixed with fibers in a ratio of 35:65 to 45:55 (w/w), and the composition-fiber mixture may be cured under vacuum at a temperature of 200° F. to 450° F. for 30 minutes to 180 minutes to form a composite.

Abstract: Provided herein are compositions, comprising polysilazane, polysiloxane, and a boron constituent. The compositions may further comprise carbon nanofibers. Also provided is a method for forming the compositions, composites formed from a composition, and a method for forming composites from a composition by mixing the compositions with fibers and curing the composition-fiber mixture.