A Malaysian scientist says she has discovered a cheap way to turn discarded rice husks into a high-tech material that could reduce electricity bills, protect buildings from bomb blasts and make airplanes and tennis rackets lighter.
Aerogel, the lightest solid known to man, was invented in 1931 by an American scientist, but its high cost has limited its use.Halimaton Hamdan, a University of Cambridge-trained chemistry professor, said her process cuts the cost of producing aerogel by 80 percent, making it so affordable that it could become a commonplace material with widespread use.
So what is aerogel and what are its interesting properties in the first place?
Nicknamed "frozen smoke" because of its cloudy appearance, aerogel is made from silica, the basic ingredient in sand, and is over 95% per cent air by volume. The result is a nearly weightless and translucent material with a white powder that seems to float inside. Aerogel can withstand mechanical pressure 2,000 times its own weight, making it suitable for bomb-proof panels. It also makes good sound-proofing material. Additionally, aerogel can also absorb oil spills and pollutants in the air - NASA fitted a space probe in 1999 with a mitt packed with the substance to catch the dust from a comet’s tail.
Summary of aerogel properties
1. Space Age nanomaterial (top 10 materials of the millenium)
2. Gel filled with air
3. Fourth state matter
4. Frozen smoke
5. Lightest solid – 3 times the density of air
6. Consists of 96% air
7. Porous amorphous solid with pore diameter of 1-30 nm
8. Large surface area – 600-900 m2 per g9. Dielectric material – thermal, electrical and acoustic insulator
And what is Maerogel?
It is a silica aerogel produced from rice huskIt is a novel nanomaterial of a highly divided state and exhibits unconventional properties which offers more cost effective methods of production and application.Aerogel has been around since 1931, but its high cost has limited its use. The new process to make Maerogel cuts the cost of producing aerogel by 80 per cent, making it so affordable that it could become a commonplace material with wide use.
Comparison between Maerogel and Aerogel
1. Maerogel is more superior in quality than the current commercial aerogel. Being an inert, non-toxic and environmentally friendly amorphous material, Maerogel possesses established physico-chemical properties which can be modified for specific applications. Silica aerogel has been used as a catcher’s mitt in spacecraft to
2. Cheaper alternative of precursor
3. Silica aerogel from rice husk
4. Simpler preparation technique
Product Features & Physical Properties of MaerogelProduct Features
1. Merogel contains pores and properties which are smaller than the wavelength of light and is the lightest solid materialknown.
2. A nanomaterial of a highly divided state and exhibits unconventional properties which offers more cost effective methods ofproduction and application.
Physical Properties
Apparent density 0.03 g/cm3
Internal Surface Area 800-900 m2/g
Mean Pore Diameter 20.8 nm
Thermal Tolerance to 500 oC, mp > 1200 oC
Thermal Conductivity 0.099 Wm-1 K-1
Some useful applications of Maerogel:
1. Dust capture for space applications - capture dust from a comet.
2. Because of being nearly weightless, aerogel is an excellent thermal insulator; particularly for the space crafts industry, where in the vacuum of space, Maerogel provides seven-fold better insulation then fiberglass. also applications in vacuum and heat insulation of hot water tanks, boilers, and refrigerators
3. It is a dielectric with potential applications as support in computer chips, active electronic materials and battery components. Also spacers in computer chips – double the speed of computers
4. Ultracapacitor technology
5. Nanocatalysts
6. Ultralightweight composites, sensors, lenses
7. Window panes – 1” layer of aerogel provides the same insulation value as 15 standard thermopanes
8. A promising material for translucent roofing and particularly potential applications in computer chips, active electronicmaterials and battery components
