Sodium silicate based aerogels via ambient pressure drying: synthesis, properties and applications

Silica aerogels are the lightest of all solid substances having a very porous internal structure, which leads to a number of interesting properties. They possess very low thermal conductivity as well as a huge internal surface area. Now a day silica aerogels are used as thermal insulator in temperature-resistance windows, refrigerators, ovens etc. They are synthesized by the supercritical or ambient pressure drying of the liquid silica gels. But , the use of expensive alkoxide precursors and supercritical drying method for the synthesis of silica aerogels restricts their large scale production. So, for the commercialization purpose sol-gel processing of sodium silicate based aerogels via ambient pressure drying is described in this context and their physico-chemical properties are studied.