One Of The Most Interesting Properties Of Silica Aerogel

Silica Aerogel is an interesting material with a very low mass, which exhibits excellent thermal properties. It has an extremely low specific heat, so that it can absorb a large amount of energy without becoming hot. This property makes it a promising candidate for insulators. Furthermore, it also exhibits a very high optical transmission, which is important for nonlinear optics.

The synthesis of Silica Aerogel in Insulation was first developed by Samuel Stephen Kistler in the 1930s. He used the gel-like material in a variety of applications, including hypervelocity particle capture and thermal insulation. In the aviation world, both civil and military, the use of this material has been extensive due to its thermal and acoustic insulation properties.

Since the discovery of this amazing material, a lot of research has been conducted to improve its performance. In the case of aerogel, this is achieved by doping it with various opacifiers. In addition, different drying methods are employed. This is particularly important because the properties of aerogels are affected by their density and porosity.

For example, if the aerogel is not dried correctly, it can lose a significant portion of its properties. A typical method involves heating the gel in an autoclave under atmospheric pressure to a temperature above its critical point. This is known as supercritical drying. This process allows the liquid phase to escape, leaving behind a highly porous and extremely low-density material.

Another way to modify the properties of an aerogel is by using an opacifier to change its transparency. For example, a hollow opacifier can be incorporated into the material to reduce its transmissivity, thereby decreasing its radiative thermal conductivity.

The opacifiers can be added to the gel during the drying process or they can be mixed with the silica during the gel formation stage. In the latter case, a composite can be created. The opacifiers can either be solid or hollow, and they can be made of any material that is compatible with the gel.

One of the most interesting properties of silica aerogel is its elasticity, which is attributed to the interparticle connections within the pearl-necklace-like fractal network. This is why it has been suggested that it can be used as a substitute for rubber. However, the elasticity of silica aerogels is not sufficiently strong to support substantial mechanical loads. Therefore, further research is needed to increase their mechanical strength.

Another area that has received a great deal of attention is the application of silica aerogel in housing and building construction. The researchers modeled an entire house, including walls and windows, to determine the impact that the material would have on its thermal insulation. The results showed that the material would reduce a home’s heating and cooling costs by about 40%. The study included detailed analysis of the flow of air, the surface temperature of each simulated wall, and the energy consumption of the home. The researchers are working to further develop this technology so that it can be used in residential buildings.