Silica Aerogel As Thermal Insulation Material

ZHENGZHOU, China - Dec. 1, 2017 - PRLog -- The microstructure of silica aerogel is effective in limiting the propagation of local heat excitation, and its solid-state thermal conductivity is 2-3 orders of magnitude lower than that of the corresponding glass state materials. Nano-pores inhibit the contribution of gas molecules to heat conduction. The refractive index of silica aerogel is close to L, and the ratio of annihilation coefficient of IR and visible light is more than 100, which can effectively penetrate sunlight and prevent ambient temperature from infrared thermal radiation, and become an ideal transparent insulating material, which has been applied in solar energy utilization and building energy conservation. By means of doping, the radiant heat conduction of silica aerogel can be reduced, and the thermal conductivity of carbon aerogels under normal temperature and pressure can be up to 0. 013w/m K, is the lowest thermal conductivity of solid materials, is expected to replace polyurethane foam as a new type of refrigerator insulation. Adding titanium dioxide can make silicone aerogel a new type of high-temperature thermal insulation, 800K thermal conductivity is only 0. 03w/m K, as a new material for military equipment will be further developed.

Because of the low sound velocity of silica aerogel, it is an ideal acoustic delay or high temperature noise material. The variable range of acoustic impedance of the material is larger (103-107 kg/m2 s), which is an ideal acoustic-resistive coupling material for ultrasonic detectors, such as commonly used acoustic resistance zp=1. 5xl07 kg/m2 s piezoelectric ceramics as ultrasonic generators and detectors, and the air resistance only $number kg/m2 s. The silicon aerogels with thickness of $number wavelength are used as acoustic resistance coupling materials of piezoelectric ceramics and air. It can improve the transmission efficiency of acoustic wave and reduce the signal-to-noise ratio in the application of the device. The preliminary experimental results show that the density of silica aerogel, which is about $literal, can increase the intensity of dB, and a higher intensity gain is expected if silica aerogel with density gradient is adopted.

In environmental protection and chemical industry. Nano-structure aerogels can also be used as a new type of gas filtration, unlike other heat insulation material (http://www.aerogelinsulationblanket.com/product-news/heat...), the pore size distribution of the material is uniform, high porosity, is an efficient gas filtration material. Because the material is particularly large compared to the table. aerogel insulation (http://www.saleaerogel.com/aerogel-ingulation/) have broad application prospects as carriers of new catalysts or catalysts.