Porous glasses from aerogels: from organic liquid to mineral materials

• Published in: Journal of sol-gel science and technology 2022-06, Vol.102 (3), p.589-595
• Main Authors: Woignier, T., Duffours, Laurent, Primera, J.
• Format: Article
• Language: English
• Subjects: Aerogels; Ceramics; Chemistry and Materials Science; Composites; Condensed Matter; cryogels; etc.; Glass; Glass ceramics; Heat treatment; Inorganic Chemistry; Materials Science; Mechanical properties; Nanotechnology; Natural Materials; Optical and Electronic Materials; Organic liquids; Original Paper: Nano- and macroporous materials (aerogels; Permeability; Physical properties; Physics; Porosity; Silica glass; Sintering; Sintering (powder metallurgy); Sol-gel processes; Synthesis; Viscous flow; xerogels
• ISSN: 0928-0707; 1573-4846
• DOI: 10.1007/s10971-022-05772-6

Due to an easy sintering stage, composite aerogels offer an alternative way to synthesize silica glass at temperatures ranging from 900 to 1200 °C, close to half the temperatures used for the glass melting process. The heat treatment is tailored to obtain fully densified or porous glasses. In this study, the kinetics of dimensional shrinkage were characterized during the sintering mechanism, and we confirmed that the viscous flow-sintering model also applies to composite aerogels. Porous glasses with a broad range of porosity and physical properties (mechanical strength, elasticity modulus, permeability) have been synthesized. The synthesis of glass-ceramics from these open pore structures is explored. Graphical abstract Highlights Synthesis of porous glasses with porosity 95–0 percent from composite aerogels. The addition of aerosil (silica powder) in the sol gel solution tailors the composite aerogels physical properties. The composite aerogels sintering is a viscous flow process described by the Scherer’s model. The mechanical properties and the permeability of the porous glasses evolves over 3 and 4 orders of magnitude, over the whole porosity range.