초록 ▼

There is provided a process for producing an aerogel which comprises lowering a pH of a water glass solution to obtain a sol, gelling the sol to obtain a hydrogel, replacing water in the gel with an organic solvent, reacting the gel with a hydrophobilizing agent having hydrophobic groups as well as

There is provided a process for producing an aerogel which comprises lowering a pH of a water glass solution to obtain a sol, gelling the sol to obtain a hydrogel, replacing water in the gel with an organic solvent, reacting the gel with a hydrophobilizing agent having hydrophobic groups as well as functional groups reactive with silanol groups in liquid phase, followed by supercritically drying; or hydrophobilizing and supercritically drying the resultant gel at the same time. Preferably, the hydrogel is prepared by ion exchanging alkali metals in the water glass solution using an ion exchange resin to obtain a sol which is subjected to suspension polymerization.

대표청구항 ▼

[What is claimed is:] [14.]a) lowering a pH value of a water glass solution to obtain a sol as a hydrosol, wherein lowering the pH value is performed by:ion exchanging the water glass solution with an ion exchange resin, wherein the ion exchange resin has a ratio of ion-exchangeable hydrogen atoms t

[What is claimed is:] [14.]a) lowering a pH value of a water glass solution to obtain a sol as a hydrosol, wherein lowering the pH value is performed by:ion exchanging the water glass solution with an ion exchange resin, wherein the ion exchange resin has a ratio of ion-exchangeable hydrogen atoms to a number of moles of alkali metals in the water glass solution (Resin:Sol) of greater or equal to about 1 (Resin:Sol>1 or Resin:Sol=1);b) gelling the sol to obtain a gel as a hydrogel, wherein gelling is performed by suspension polymerizing the sol by adding the sol dropwise to a poor solvent which does not dissolve the gel, and stirring the poor solvent; andc) simultaneously performing the steps of:reacting the gel with a hydrophobilizing agent, wherein the hydrophobilizing agent has hydrophobic groups as well as functional groups reactive with liquid phase silanol groups; and drying the gel under supercritical conditions, wherein a supercritical fluid is used as a dispersion medium.