Production and Characterization of SiOC Ambi/Aerogels
ICIN O. 1, SORARU G. 2, VAKIFAHMETOGLU C. 1
1 Department of Materials Science and Engineering, Izmir Institute of Technology, 35430, ?zmir, Turkey; 2 Department of Industrial Engineering, University of Trento, Via Sommarive 9, 38123, Trento, Italy
Porous materials have been of great interest in various technological processes such as biomedical, catalysis, filtration (gases, liquids including molten metals), and thermal management. Porous and high surface area silicon oxycarbide (SiOC) aero/ambigels were synthesized using economic and commercially available siloxane resin, polymethylsilsesquioxane. First, the preceramic gels were obtained via cross-linking in an autoclave, followed by a drying conducted in ambient pressure (ambigels) or under CO2 supercritical conditions (aerogels). Finally, pyrolysis at different temperatures (600-800-1000 oC) resulted in the formation of SiOC aero/ambigels. The highly porous components were characterized by SEM, TGA, XRD, FTIR, and N2-sorption analysis. The total porosity of the samples always remained around 80%, the specific surface area values were between 274-917 m2/g, and the pore volume of 1.45-4.99 cm3/g, depending on the processing conditions.