Silica aerogels with enhanced durability, 30-nm mean pore-size, and improved immersibility in liquids

Structure and mechanical properties of silica aerogels and xerogels modeled by molecular dynamics simulation

“…For instance, the production of crack-free monolithic tiles becomes difficult due to the brittleness of the material [11] which affects its application in glazing systems where cracks are associated with light scattering [12,13]. Also the use of aerogels as reaction platforms requires very delicate handling, and their weakness limits the usefulness of the material in this context [14].…”

Modified aging process for silica aerogel

“…doi:10.1016/j.jmatprotec.2008.04.009 and stiffness of the wet gel by rebuilding the network via further hydrolysis, condensation and specific reaction of these monomers. Silica aerogel cured in methanol exhibits high elastic modulus and hardness (Lucas et al, 2004;Haereid et al, 1996). To control the composition of aging solution can tune the texture of silica gel, and the gels with more homogeneous pore size distribution can be obtained in less-concentrated poly-TOES solution (Reichenauer, 2004).…”

Correlation between the elastic modulus and heat transport along the solid phase in highly porous materials: Theoretical approaches and experimental validation using polyurea aerogels

“…Symbol c 11 ,c 44 Elastic constants C 1 ,C 2 Constants referring to the geometrical arrangement within a unit-cell E Young's modulus E0…”

“…While the basic unit-cell model successfully predicts the macroscopic properties of highly porous materials that are characterized by a regular microstructure (e.g., honeycombs or foams), scaling laws of porous materials with irregular microstructure (e.g., statistically isotropic) significantly deviate from the linear and quadratic dependency found in Eqs. (1) and (2). For aerogels, the heat transport along its solid framework is rather found to scale with an exponent ˛A erogel of 1.2-1.5 and the elastic modulus scales with an exponent Aerogel of 2.4-4 [10,11]:…”

“…Insulations based on nano-porous materials show a superior thermal conductivity of 0.012 mW/mK that is mainly due to the heat transport via the solid phase [1]. On the other hand, the mass-normalized mechanical stiffness of these materials are low, too, restricting the field of technical application [2]. In this case, it would be of major interest, if the elastic modulus can be increased while keeping the thermal conductivity of the material low (decoupling of these two properties).…”