What are Aerogels?

Aerogels were first developed in the 1930s, but it was not until the late 1980s/early 1990s that research into these materials accelerated with the introduction of carbon aerogels.

As low-density, solid-state materials, aerogels are produced by replacing the liquid component of a gel with gas, retaining its structure whilst significantly reducing its density. Another term for this innovative class of material is “liquid smoke” due to how light scatters through it and its semi-transparent appearance.

The gel’s liquid component is extracted by supercritical drying, wherein the liquid is drawn out of the gel in a supercritical state. In this state, the distinction between liquid and gas phases within the material no longer applies. Compared to conventional evaporation, supercritical drying does not cause the solid matrix to collapse.

Aerogels are extremely strong but prone to shattering. These materials possess remarkable properties such as high strength (they are able to support structures many times their weight,) lack of electrical conductivity, low dielectric constant, high specific surface area, and outstanding thermal and acoustic insulation.

These remarkable materials can be made from a variety of precursor materials, such as silica, carbon, organic polymers, iron oxide, copper, and gold. Once prepared, very little of the solid material remains, and the structure of the final material is composed of up to 99.8% air.

How Can Aerogels Be Applied in Buildings?

The favorable properties of aerogels make them suitable for innovative applications in a number of industries, including construction. As the sector seeks to fulfill its net zero obligations and economic challenges and embrace new technologies, research into aerogels for use in buildings has accelerated in recent years.

Aerogels possess outstanding thermal and acoustic insulation properties and fire retardation possibilities. They can be applied in soundproofing, fireproofing, and as insulation for enhancing the energy efficiency of buildings either in new structures or in retrofitting existing ones.

Sustainability Compared to Other Materials

However, one area where aerogels are significantly more beneficial for building projects is their sustainability. They are user-friendly, non-toxic, recyclable, and reusable. 

Many conventional materials used in construction for the same purposes as aerogels are difficult to recycle or dispose of at the end of their lives, which is especially problematic as the industry seeks to improve its green credentials. Aerogels could significantly contribute to the future sustainability of the construction sector.

Final Thoughts

Aerogels could revolutionize the construction industry, providing new, highly efficient, cost-effective, and environmentally friendly materials for applications such as thermal insulation, energy-efficient devices, air purification, glazing, soundproofing, fire retardants, and some structural elements in new builds and heritage buildings.

Source：AZO BUILD