A STUDY ON THE DEVELOPMENT OF MULLITE FIBERS USING THE SOL-GEL PROCESS

Abstract

To produce transparent composite polymeric mullite sol, polymeric alumina sol was synthesized from aluminum sec-butoxide mixed with iso-propanol, acetylacetone, water and hydrochloric acid. Polymeric silica sol derived from tetraethyl orthosilicate (TEOS), iso-propanol, water and hydrochloric acid was then added; magnesium nitrate (Mg(NO3)2.6H2O) and boric acid (H3BO3) were also used as additives to the composite sol. Short and long fiber spinners were developed at the laboratory scale. By use of these spinners, short and long mullite fibers were drawn from the composite sol after heat treatment. A pH meter. a viscometer, FT-IR, XRD and SEM were used to study the properties and microstructures of the fibers.