Binder-free bulk silica aerogel material, method of producing the same and uses thereof

Abstract

A method of preparing a binder-free bulk silica aerogel material, comprising the steps of: (i) providing an amount of granular silica aerogel material, and (ii) carrying out a curing step wherein the granular silica aerogel material is contacted with a curing medium, thereby converting the granular silica aerogel material to the bulk silica aerogel material. According to the invention, the granular silica aerogel material is hydrophobic, and the curing medium is an aqueous curing medium which is either acidic with a pH<4 or basic with a pH>10. A resulting binder-free bulk silica aerogel material comprises silica aerogel granules which are interface-bonded and has the following properties: a thermal conductivity below 24 mW/(m·K), a compressive strength of at least 5 kPa, a 3-point flexural stress (σf), determined with a specimen having a longest dimension which is four times the specimen thickness, of at least 0.5 kPa.

Dependencies are inferred from the claim text.