Synthesis of continuous silicon carbide-titanium carbide hybrid fibers through sol-gel processing

Abstract

Silica-titania-phenolic resin hybrid fibers have been prepared from ethanol solutions of tetraethoxysilane (TEOS), titanium tetrakis(2,4-pentanedionate) (TTP), and novolac-type phenolic resins, where water and HCl have been added at a (TEOS + TTP):water:HCl molar ratio of 1:2:0.01, by sol-gel processing. The Si-to-Ti atomic ratio of the hybrid fibers was varied down to 10.4 by changing the amounts of TEOS and TTP in the starting solutions. Carbothermal reduction of both silica and titania components of the hybrid fibers has taken place at 1500 °C in an Ar flow, resulting in the formation of continuous β-silicon carbide-titanium carbide hybrid fibers with Si-to-Ti atomic ratios varied down to 9.9.