SEAgel/Aerogel Presentators: Maria Damaz Maria Orozco Engineering 45: Materials Semester Project Presentation Date: December 9 th 2009

Purpose Background Applications Compare SEAgel and Aerogel Videos

Safe Emulsion Agar Gel Invented in the Lawrence Livermore National Laboratory by Robert Morrison. –“ghost like substance”, “blue smoke”, “lighter than air solid” –Lighter than air (10% lighter than air and aerogels !!!!!) –Made from agar –Edible –Biodegradable –Pores are 2-3 micrometers in diameters (low thermal conductivity) –Density is about mg/cm3 –Covered under two patents (“Biofoam”) and (“Biofoam 2”) Picture courtesy of 4engr.com

How is it made? 1.Agarose (food thickener) is dissolved and emulsified. 2.The emulsion is cooled to a gel like substance. 3.Emulsion is freeze and then freeze-dried, ending in seagel. Density is determined by the amount of agarose –Strength increases with increasing density

Possibilities Replace balsa wood (sound barrier), insulation in refrigerators or oil tankers Packaging material instead of plastic chips Time releasing medication, insecticides or fertilizers Agarose has a relative low cost!

Aerogel: Aerogel is a manufactured material with the lowest bulk density of any known porous solid. It is derived from a gel in which the liquid component of the gel has been replaced with a gas. Therefore, making the result an extremely low-density solid with several remarkable properties, effectiveness as a thermal insulator and its extreme low density. It is nicknamed frozen smoke, solid smoke or blue smoke due to its translucent nature and the way light scatters in the material; however, it feels like expladed polystyrene (styrofoam) to the touch. Aerogels posses the lowest density and highest internal surface aread of any known solid material, which makes them extremely high performance material for collision, damping, acoustic and thermal insulation, structural support and surface chemistry.

Types of Aerogels: Silica: Silica aerogel is the most common type of aerogel and the most extensively studied and used. It is a silica-based substance, derived from silica gel. The world's lowest-density solid is a silica nanofoam at 1 mg/cm 3, which is the evacuated version of the record-aerogel of 1.9 mg/cm 3.The density of air is 1.2 mg/cm 3. Silica aerogel strongly absorbs infrared radiation. It allows the construction of materials that let light into buildings but trap heat for solar heating. It has remarkable thermal insulative properties, having an extremely low thermal conductivity: from 0.03 W/m·K down to W/m·K, which correspond to R-values of 14 to 105 for 3.5 inch thickness. For comparison, typical wall insulation is 13 for 3.5 inch thickness. Its melting point is 1,473 K (1,200 °C or 2,192 °F). Silica aerogel holds 15 entries in Guinness World Records for material properties, including best insulator and lowest-density solid. Carbon: Carbon aerogels are composed of particles with sizes in the nanometer range, covalently bonded together. They have very high porosity (over 50%, with pore diameter under 100 nm) and surface areas ranging between 400–1000 m²/g. They are often manufactured as composite paper: non-woven paper made of carbon fibers, impregnated with resorcinol-formaldehyde aerogel, and pyrolyzed. Depending on the density, carbon aerogels may be electrically conductive, making composite aerogel paper useful for electrodes in capacitors or deionization electrodes. Due to their extremely high surface area, carbon aerogels are used to create supercapacitors, with values ranging up to thousands of farads based on a capacitance of 104 F/g and 77 F/cm³. Carbon aerogels are also extremely "black" in the infrared spectrum, reflecting only 0.3% of radiation between 250 nm and 14.3 µm, making them efficient for solar energy collectors.

Properties: Though with a ghostly appearance like an hologram, aerogel is very solid. It feels like hard styrofoam to the touch. The aerogels feel like a light but rigid foam. They are rigid, dry materials. Pressing firmly enough will cause a catastrophic breakdown in the sparse structure, causing it to shatter like glass. Its impressive load bearing abilities are due to the dendritic microstructure. They are good thermal insulators. They almost nullify the 3 methods of heat transfer (convection, conduction and radiation). They are good conductive insulators because they are composed almost entirely from a gas (gases are very poor heat conductors). They are good convective inhibitors because air cannot circulate through the lattice.

Properties: Carbon aerogel is a good radiative insulator because carbon absorbs the infrared radiation that transfers heat at standard temeperature. One inch thickness of aerogel provides the same thermal insulation as 30 panes of window glass. A block of aerogel the size of a person would weigh roughly one pound but support the weight of almost a ton. A thin sheet of this nearly translucent material insulates better than yards of fiber glass batting. Another photo illustrating the excellent insulating properties of aerogel. The matches on top of the aerogel are protected from the flame underneath. Low thermal conductivity. Refractive index and sound speed. Ability to capture fast moving dust particles. It can absorb pollutants such as crude oil. A flower is sitting on a piece of aerogel which is suspended over a bunsen burner. Aerogel has excellent insulating properties, and the flower is protected from the flame.

Uses: Work as a sponge, to clean up spills. Aerogel materials are some of the most effective insulation fillers for vacuum application because of the rapid drop of the thermal conductivity as the ambient gas pressure inside of the pores is lowered. It is made out of silica and used for NASA missions to collect tiny floating comet dust particles. In 1999 the space agency fitted its stardust space probe with a milt packed full of aerogel to catch the fust from comet’s tails. Mark Krajweski, a senior scientist at Aspen Aerogel, believes that a 18 mm layer of aerogel will be sufficient to protect astronauts from temperatures as low as -130 *C. Aerogel is described by scientists as the “ultimate sponge” with millions of tiny pores on its surface making it ideal for absorbing pollutants in water.

How to make aerogel: Aerogel is pure silicon dioxide and sand, just as glass, but aerogel is a thousand times less dense than glass because it is 99.8% air. It is prepared like gelatin by mixing a liquid silicon compound and a fast-evaporating liquid solvent, forming a gel that is then dried in an instrument similar to a pressure cooker. The mixture thickens, and then careful heating and depressurizing produce a glassy sponge of silicon. (website that goes into detail on how to make aerogel) To the left is the critical drying process that scientists have to follow to be able to create aerogel.

Aerogel applications: Energy efficient windows Sound insulators Super capacitors Nearly transparent, scatters blue light Resistant to structural breakdown caused by solar radiation, radioactivity and ozone Non toxic Non flammable Destroyed by contact liquid Can be shattered by rapid pressure changes Waste gas capture before emission to atmosphere Crucible material for microgravity solidification research

Aspen Aerogel Inc: Aspen Aerogel Inc is the top aerogel-based company in the world which provides thermal management and energy conservation insulation solutions for a variety of industries. Their insulation products are up to eight times more effective than traditional insulation materials. They develop, manufacture and market nanotechnology materials for conserving energy. Their aergoels provide thermal insulation, acoustic insulation, infrared supression and shock absorption. The company serves various markets such as: –Appliances –Buildings and homes –Canadian oil sands –Technologies –Military and aerospace devices –Apparel and footwear –LNG shipping and storage –Transportation –Process equipment, piping, and vessels; and building/construction and automotive

Cool Facts: Recognized by Guiness World Records as the solid with the lowest density times less dense than glass. It is 99.8% air Can withstand a direct blast of 1kg of dynamite and protect against heat from a blowtorch at more than 1300*C Being tested for bombproof housing and armour for military vehicles Dunlop, sports equipment has come up with tennis rackets strengthened with aerogel, to deliver more power. Fashion designer created a line of jackets that later on had to withdraw from the fashion market because he had lots of complaints that they were TOO HOT!! I cubic centimeter of aerogel would fill an area the size of a football field

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