Aerogel is the world's lightest solid material and exhibits the lowest thermal conductivity. Aerogel has more than twice the insulating performance of still air. It also has an open structure that allows vapour to readily diffuse through its matrix. Incorporating aerogel into existing or new insulation materials can displace air and replace it with the superior performance of aerogel. Aerogel additives enable insulation boards, blankets, plasters, coatings and composites to achieve previously unattainable thermal performance. These aerogel composites can be used for thermal insulation and passive fire protection of structural elements in buildings.
Silica aerogels are also excellent acoustic insulators. The propagation of an acoustic wave is attenuated both in amplitude and velocity because the wave energy is progressively transferred from the gas to the aerogel solid network, over the entire aerogel work piece thickness. The acoustic properties of aerogels make them effective insulators against noise. By combining multiple layers with different granular sizes, average attenuations of −60 dB has been found for a total thickness of only 7 cm.
Aerogels are a special type of solid material with nanometre-scale pores, 1/3000th the width of a human hair. Porosity is in excess of 90%, in some cases as high as 99.9%, and densities can be as low as 3 kg/m3. Aerogels are essentially puffed-up sand and are often termed frozen smoke. Their thermal conductivity (0.014 W/mK at room temperature) is the lowest of any solids, and they also have good transparency. The longitudinal acoustic velocity is typically of the order of 100 m/s, which makes silica aerogels suitable for applications in acoustic devices. And aerogels have the lowest refractive index, and dielectric constant of all solid materials.
In the past, aerogel has been mostly confined to small-scale applications in aerospace. But it's now increasingly being used for large, building-integrated applications to reduce energy consumption, sparking new interest from both start-ups and large insulator makers.
The technology is fairly straightforward and seems like an obvious choice for building owners and architects looking for a simple solution to cut energy costs. Aerogel insulation can help improve energy performance while adding to occupants comfort and satisfaction. The technology can be applied on most of the buildings including HDB flats, shop houses, commercial buildings, industrial buildings, landed housing and non-landed housing. Most importantly, the technology can be applied to both old and new buildings.
The aerogel insulator will certainly have a significant place in future green building materials for architectural, vehicle, aircraft, spacecraft and marine insulation, and create a market potentially worth billions of dollars.
With the application of the aerogel product, the following benefits could be obtained: