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Showing 1 to 20 of 80 for “"Aerogels."”.
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Aerogels as diverse nanomaterials
"Aerogels are 3-D light-weight nanoporous materials pursued for their low thermal conductivity, low dielectric constant and high acoustic attenuation. Those exceptional macroscopic properties of aerogels are dependent on the chemical nature of nanoparticles, complex hierarchical solid skeletal …
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Optothermal Characterization of Nanoparticle Infused Aerogels
Here, custom fabricated nanoparticle infused aerogels are presented as a potential material to achieve super insulating and transparent opto-thermal properties. By incorporating nanoparticle solutions within the silicon dioxide (SiO₂) aerogel during the sol-gel process, unique monolithic samples …
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NOVEL SYNTHETIC METHODS AND APPLICATIONS OF POROUS MATERIALS: AEROGEL FOAMS, METALLIC AEROGELS, AMORPHOUS AND GRAPHITIC CARBON AEROGELS
… such as polymeric aerogel foams, pure metallic aerogels, amorphous and graphitic carbon aerogels, and their applications. I. Polyurethane based aerogel foams were synthesized with an aliphatic triisocyanate and ethylene glycol through a pressurized (7 bar) sol-gel method. The foam-like structure …
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Characterizaton of Triethoxyfluorosilane and Tetraethoxysilane Based Aerogels
Aerogels are highly porous, low dielectric constant (low k) materials being considered by the semiconductor industry as an interlayer dielectric. Low k materials are needed to overcome capacitance problems that limit device feature sizes. Precursors triethoxyfluorosilane (TEFS) and …
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Aerogels and films through free radical polymerization
"Aerogels are porous lightweight materials, unique among all solids in terms of low density, low thermal conductivity, low dielectric constants and high acoustic attenuation. The penalty for those exceptional properties is fragility. That issue has been addressed by bridging covalently …
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Polyurea aerogels: From nanoscopic to macroscopic properties
… quantitatively. In this context, polyurea aerogels were chosen as a model system with demonstrated potential for rich nanomorphology and being guided by a statistical Design-of-Experiments model, a large array of materials (208) with identical chemical composition, but quite different …
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Subambient Passive Cooling Enabled by Polyethylene Aerogels
… and optimization of polyethylene aerogels to achieve a low thermal conductivity material with high solar reflectance and infrared transmittance. We then theoretically and experimentally investigate the benefits of using polyethylene aerogel covers in outdoor radiative coolers …
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A tour-de-force in polymer crosslinked aerogels
… density and high porosity, polymer crosslinked aerogels stand as the most promising nano-engineered examples. Covalent attachment of polymers and bridging of skeletal nanoparticles of typical aerogels is demonstrated by using surface initiated polymerization (SIP) with a bidentate free-radical …
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Nanomorphology dependent optical and mechanical properties of aerogels
<p>"Aerogels are very low density, light weight open pore materials. A hypothesis that is under intense current investigation by the scientific community states that the mechanical properties of nanostructured polymers depend on their nanomorphology. Aerogels are nanostructured ultra-lightweight …
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Development of thermally stable aerogels for aerospace applications
Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2023-09-01 without embargo terms
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Thermoelectrics and aerogels for solar energy conversion systems
… must be suppressed to achieve high eciency. Aerogels, which are stable ultra-low density foams, can suppress radiative and convective losses. It is shown that aerogel-based solar thermal receivers can increase the eciency of traditional solar thermal electricity and hot water generation. …
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One pot synthesis of metal, carbides and polymeric aerogels
… assemblies of nanoparticles are referred to as aerogels, and typically are derived from supercritical fluid (SCF) drying of wet-gels. Aerogels are generally fragile materials, but that issue has been addressed successfully by X-aerogels, in which the inorganic nanoparticle framework plays the …
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Isocyanate-derived organic aerogels: polyurethanes, polyureas, polyamides and polyimides
"Aerogels are 3D assemblies of nanoparticles with high open porosity and high surface area, and are pursued for their low density, low thermal conductivity, low dielectric constant and high acoustic attenuation. The foundation for those exceptional properties is their complex hierarchical solid …
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Characterization of Methyltrimethoxysilane Sol-Gel Polymerization and the Resulting Aerogels.
… origins of this high value were suggested. Aerogels dried by supercritical CO2 extraction were characterized by FTIR, 13C and 29Si solid-state NMR and nitrogen sorption. The existence of three residual groups (Si-OH, Si-OCH3, and Si-OC2H5) was confirmed, but their concentrations are very low …
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Nanostructured Polymer-Derived Ceramic Aerogels for Environmental and Energy Applications
… and scaffolds. In such a scenario, ceramic aerogels are ultraporous materials possessing high surface areas, low density and pore size distributions that easily reach few nanometers while maintaining rather high porosities, generally above 90%. Hence, when compared with other porous …
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Enhancement of fluidization and filtration using nanoparticle agglomerates and aerogels
Previous works have classified the fluidization behavior of nanoparticles as Agglomerate Particulate Fluidization (APF) and Agglomerate Bubbling Fluidization (ABE). These fluidization behaviors are quite different in regard to the fluidized bed expansion, the presence of bubbles and the smoothness …
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Radiative transport in transparent aerogels for solar thermal energy applications
… we explored the development of transparent aerogels for enhancing solar-thermal energy conversion. We established and validated a modeling framework to understand the fundamental light transport within an aerogel sample and yield helpful guidance for material development. We performed …
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Rational Design of Poly(phenylene sulfide) Aerogels Through Precision Processing
… DPA from the gel network creates monolithic PPS aerogels, one of few physically crosslinked polymer aerogel systems comprised of a high-performance thermoplastic. In this work, specific properties of PPS aerogels were controlled through the manipulation of various processing parameters, such as …
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Ruthenium-Chromium Oxide Aerogels Oxygen Evolution Electrocatalysts: Structure, Activity and Stability
… that chromium introduced into ruthenium oxide aerogels provides high surface area and mesoporosity and enhanced OER activity, and the structure and properties can be modified by thermal treatment temperature.
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Electronic transport and photoconductive properties of resorcinol-formaldehyde-based carbon aerogels
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Physics, 1995.
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