Patent ID: 6339034
Filing Date: 2002-01-15
Classification: C04B

Abstract:
A process of preparing an oxidation-stable, high temperature, porous ceramic insulation which comprises reacting in a liquid medium effective amounts of (a) at least one tetraalkoxy silane having the formula:Si(OR1)4 wherein R1 is a saturated or unsaturated organic radical having 1 to 12 carbons and (b) at least one dialkoxy silane having the formula:(R2O)2â€”Siâ€”R4R3 wherein R2 is a saturated or unsaturated organic radical having 1 to 12 carbons and R4 and R3 are saturated or unsaturated, either the same or different organic radicals having 1 to 12 carbons to obtain a siloxane gel drying said gel and (c) subsequently pyrolyzing the siloxane gel in an inert atmosphere at temperatures ranging from about 900Â° C. to 1500Â° C. to produce the porous ceramic insulation.