Living Reference Work Entry

Handbook of Sol-Gel Science and Technology

pp 1-27

Date: Latest Version

Aerogel Processing

  • Thierry WoignierAffiliated withIMBE, CNRS, IRD, Aix Marseille Université, Avignon UniversitéIRD - Campus Agro Environnemental Caraïbes Email author 
  • , Jean PhalippouAffiliated withLaboratoire Charles Coulomb, Université Montpellier 2
  • , Florence DespetisAffiliated withLaboratoire Charles Coulomb, Université Montpellier 2
  • , Sylvie Calas-EtienneAffiliated withLaboratoire Charles Coulomb, Université Montpellier 2


One of the problems largely commented in the sol–gel science is how to make large bodies, because gels tend to crack during drying. The drying stresses are attributed to capillary phenomena and differential strain which result from a pressure gradient in the pore liquid. By the supercritical drying (SCD), the capillary stresses are eliminated and monolithic aerogel can be obtained. This chapter focuses on silica aerogel, the most studied aerogel. It presents an overview of the supercritical drying techniques, but also some of the remarkable aerogel properties (optical, mechanical, thermal and acoustical, etc.) with respect to its peculiar microstructure.

The chapter briefly presents other kinds of aerogels (oxides and chalcogenide aerogels, composite aerogels, organic aerogels, etc.) and a panel of potential applications.