Aerogel powder

Stark, R. W., and Drobek,T. (1998), Determination of elastic properties of single aerogel powder particles with the AFM, Ultramicroscopy, 75(3), 161-169. 

Lee K, Gould G. Aerogel powder therapeutic agents. International patent publication WO 02/051389, 2002. 

Figure 9 Thermal conductivity X as a function of temperature for a CFC-blown PU foam (triangles), an opacified SiOa aerogel powder (squares), an opacified monolithic Si02 aerogel (circles), and a monolithic RF aerogel (exes). The solid lines are guides to the eye.

Evacuation reduces these values to below 0.009 W/(m-K). The best values for aerogel powders at 300 K are 0.002 W/(m-K). Thus these materials can be considered most suitable for application in high-performance insulations, for example in a NaS battery or in other high-technology insulations for which large dwell times are required. 

R. W. Stark, T. Drobek, M. Weth, J. Fricke, and W. M. Heckl, Determination of Elastic Properties of Single Aerogel Powder Particles with the AEM, Ultramicroscopy, 75, 161-169 (1998). 

Drying Here, water and alcohol are removed at moderate temperatures (<470K), leaving a hydroxylated metal oxide with residual organic content. If the objective is to prepare a high surface area aerogel powder of low bulk density, the solvent is removed supercritically. 

Measurement of runoff velocity. The runoff velocity of liquid droplets on an inclined surface coated by the superhydrophobic silica aerogel powder was quantified by recording... 

Bhagat and coworkers [28] have employed a waterglass/HMDS coprecursor method to synthesize superhydrophobic silica aerogel powders in a total preparation time of less than 5 h. 

Bhagat, S. D. Kim, Y.-H. Suh, K.-H. Ahn, Y.-S., Yeo, J.-G. Han, J.-H., Snperhydrophobic silica aerogel powders with simultaneous surface modification, solvent exchange and sodium ion removal from hydrogels, Micropor. Mesopor. Mater., 2008, 112, 504-509... 

Chen L, Zhu J, Liu Y, Cao Y, Li H, He H, Dai W, Fan K (2006) Photocatalytic activity of epoxide sol-gel derived titania transformed into nanocrystaUine aerogel powders by supercritical drying. J Mol Catal A... 

Figure 13.11. Room temperature gram magnetic susceptibilities, % of rare earth sol-gel materials as a function of the atomic number showing the expected trend for pure compounds A. %s correlate linearly with the susceptibilities of the pure oxides B. reflecting the stoichiometric similarity within each series of materials. Slopes are proportional to the relative abundance of the metal ions. Inset in A Polyurea-crosslinked dysprosium aerogel powder picked up by a 1-cm diameter Nd-Fe-B magnet.

Beds of aerogel granulate or powder are used for technical thermal insulation (Part 15), because they offer specific advantages in comparison to standard insulation materials, e.g., they can be poured into complicated shaped cavities. Opacified aerogel powders and granulates are used as thermal insulation in space applications [55], automotive applications... 

Figure 23.24. Effective total thermal conductivity of evacuated opacified silica aerogel powders (gas pressure Pg < 0.01 Pa) with different weight percents of opacifier (0/5/10% carbon black). The specimens were loaded with an external pressure of 0.1 MPa [60, 61].

Rettelbach, T., Saeuberlich, J., Korder, S. and Fricke, J., Thermal conductivity of IR-opacified silica aerogel powders between 10 K and 275 K. Journal of Hiysics D Applied Physics, 1995. 28(3) p. 581-587. Rettelbach, T., Der Warmetransport in evakuierten Pulvem bei Temperaturen zwischen 10 K und 275 K, Dissertation, University of Wiirzburg / Germany, 1996... 

Set up of the first domestic production line of silica aerogel powders. It passed the authentication of Zhejiang Science and Technology Bureau. A committee made up of... 

The company has developed several series of products, such as super-thermal insulation flexible felts, thermal insulation panels, thermal insulation cylinders and special-shaped parts, translucent thermal insulation panels, siUca aerogel powders and particles. These products can be widely applied in aerospace and aeronautics, metallurgy, chemical plant installations, oil pipes, refrigerators, cars, ships, buildings, etc. 

There are studies to develop better and much safer insulating products for the future homes, such as aerogels, powder-filled/evacuated/vacuum insulation panels, and phase change materials. 

Finally, portions of the untreated (raw) aerogel powders were thermally treated in a U-tube reactor. The media applied were air, air followed by hydrogen, or hydrogen. The temperatures ranged from 473-773 K. 

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