The Utility Of Silica Aerogel

Aerospace materials

Silica Aerogel in Insulation is an ultra-light material derived from silica gel and is the lowest-density solid known to man at about 1 mg/cm3. It appears semi-transparent due to Rayleigh scattering of short wavelengths of visible light in its dendritic structure, making it appear bluish against dark backgrounds and whitish against bright ones. It is also very strong structurally. Pressing it lightly does not leave even a minor mark, but pressing extremely firmly causes the gel to shatter like glass.

This low-density makes it a perfect thermal insulation, which has been widely used in the building industry. In order to improve the durability of aerogel, it is often reinforced with polymers and other materials. Polymer reinforcement increases its strength, elasticity and other mechanical properties and can significantly improve its thermal insulation performance. There are two main methods of introducing polymers into the silica network to promote their reinforcement: using alkyl-linked bis-silanes or by utilizing the in situ oxidized layer of silicon carbide as the adiabatic phase. Both of them have been shown to enhance the thermal insulation performance of silica aerogels significantly.

Besides its excellent thermal insulation, silica aerogel is also highly breathable. The pore size distribution and the porosity of aerogels vary by preparation method, but the average pore diameter is about 0.6 nm. In addition, the index of refraction of silica aerogel is close to one, which means that it can be used as an optical transmission medium.

Military materials

Silica aerogel can be used as a lightweight heat-insulating material for military protective clothing. Moreover, it can also be used to prevent infrared radiation and protect against electromagnetic waves. In this way, it can greatly enhance the combat capabilities of soldiers. In addition, it is possible to make the military protective clothing multifunctional by incorporating silica aerogel into other materials such as carbon fiber or boron nitride.

This multifunctionality will greatly increase the utility of silica aerogel. It will enable it to meet the needs of various applications, including electronics, construction, air and water purification, sensing, catalysts, biomedical, and food packing. It can also be combined with other materials to improve its performance, such as far-infrared radiation shielding and chemical resistance.

Silica aerogels have great potential for use in aerospace applications because of their low mass and thermal conductivity, as well as their ability to withstand high temperatures and extreme pressures. However, their low compressive modulus and tensile strength limit their use in some applications. Therefore, researchers have been working to develop techniques to strengthen silica aerogels. One such technique is adsorption of fracture energy, which can help to improve the elastic response of silica aerogels and make them more durable. In addition, other techniques can be used to modify the pore structure of silica aerogels to increase their strength and flexibility. This will enable them to better withstand the stresses and strains that can occur in aerospace applications. In particular, a new technique called in situ network framework reinforcement has been developed to optimize the pore structure of aerogels.