1. AEROGEL

3. HISTORICAL ORIGINS
Aerogel was invented some time between 1930 by Dr Samuel Stephen Kistler
But actual commercial production was
not done till late 1990s .

4. WHAT IS AEROGEL …?
Aerogels are a diverse class of porous, solid materials which exhibit an uncanny array of extreme materials properties
Silica Aerogel
Organic and Carbon Aerogels
Metal Oxide Aerogels
Metal Aerogel

5. SPECIAL PROPERTIES OF AEROGEL
extraordinarily strong in compression
highest compressive strength to weight ratio of any known material
Very high thermal insulation

6. RECORDS HELD BY AEROGEL
Lowest density solid ( g /cm3)
Lowest optical index of refraction (1.002)
Lowest thermal conductivity (0.016W /mK)
Lowest speed of sound through a material (70 m/s)
Lowest dielectric constant from 3-40 GHz (1.008)

7. MANUFACTURING OF AEROGEL
Preparation of a hydrogel (gels with water as a solvent) in reaction of sodium silicate with hydrochloric acid.
Removal of sodium and chlorine ions. This step involves a long and tedious soaking of the gel.
Converts the hydrogel into alcogel by replacing water with ethyl alcohol in a lengthy process of solvent replacement.
Drying at above critical conditions for ethyl alcohol.
The balanced chemical equation for the formation of a silica gel from TEOS is:
Si(OCH2CH3)4 (liq.) + 2H2O (liq.) = SiO2 (solid) + 4HOCH2CH3 (liq.)

9. SUPERCRITICAL DRYING

10. Surface Tension and Capillary Stress Shrinkage
The Critical Point
Surface Tension and Capillary Stress
Shrinkage
Properties of Supercritical Fluids
CH3OH Methanol C atm
CO2 Carbon dioxide C atm

11. High-Temperature Supercritical Drying
Most organic solvents have relatively high critical temperatures of °C with critical pressures of atm, and are dangerously flammable and potentially explosive at these conditions.

12. Low-Temperature Supercritical Drying from Carbon Dioxide (the Hunt Process)
Instead of using flammable, explosive solvents, a safer, non-flammable solvent can be used instead–carbon dioxide. In this process, the organic solvent in a gel is replaced with liquid carbon dioxide by soaking. The liquid carbon dioxide can supercritically extracted at a much lower temperature (31.1°C) than an organic solvent and without the risk of combustion.

14. APPLICATIONS SPACE APPLICATIONS ELECTRICAL AND ELECTRONIC APPLICATIONS
ACOUSTICAL AND MECHANICAL APPLICATIONS  
OPTICAL PROPERTY APPLICATIONS  
OPTICAL PROPERTY APPLICATIONS
THERMAL APPLICATIONS ( Superinsulator)

15. NASA STARDUST COLLECTOR

17. THERMAL INSULATION
Conduction
Convection
Radiation

18. HIGH STRENGTH TO WEIGHT RATIO
Low Density
High Compressive
Strength

19. OPTICAL PROPERTIES

20. Conclusion
Aerogel will probably be a common household name in the next decade although it is not yet ready for commercial use.
Eco friendly building design ( replace glass pane)