Developing New Ideas for Preparation and investigations of silica aerogels

The aim of this paper create a very porous and less dense structure called silica aerogels through sol-gel process, and drying it through a Super Critical Drying process and then investigation of new surface modification treatments and achieve to super Soundproofing and super thermal insulator. The Precursor needed for this process included : TEOS(Tetraethyl orthosilicate), Ammonium Fluoride, Ammonium Hydroxide, Ethanol, n-Hexane, TMCS(Trimethyl chlorosilane) and Deionized Water.In the first step of preparation an innovative idea was introduced to produce sol-gel solution.in this step surface modification solution composed of (TMCS/n-Hexane/ETOH) added to sol-gel solution.in next step for remove the catalyst and water from the solution to purifying it , gel phase added to ethanol .In final step gel phase is putting onto the autoclave and a inert gas (i.e CO2) with 72 3 barr pressure and 32 5 °c temperature is blowing for sufficient time to evaporating and removing solvent from structure and then Reduce the pressure of tank to atmospheric pressure and the silica aerogels was produced .the Super Critical Drying process is done to Substitutes liquid entrapped in aerogels structure whit gas in conditions that Surface tension and Capillary forces was disappeared, in such a way that the Fine pores of nanostructured martial was remaind.

کلیدواژه ها:

Silica Aerogel ، sol-gel ، porous ، Surface Modification ، Super Critical Drying ، Soundproofing