博文

目前显示的是 十二月, 2017的博文

Five Characteristics of Silica Aerogels

图片
Silica Aerogels  is a very good thermal and thermal insulation properties of lightweight nano porous amorphous solid material, the porosity of up to 80-99.8%, the typical pore size of 1-100 nm, the specific surface area of ​​200- 1000 m2 / g, while the density can be as low as 3 kg / m3, and the room temperature thermal conductivity can be as low as 0.012 W / (m • k). It is because of these characteristics that Aerogels materials have a wide range of potential applications in thermal, acoustic, optics, microelectronics and particle detection.        Silica Aerogels Properties        1, heat insulation        The silica Aerogels material has a very low thermal conductivity of 0.013-0.016 W / (m · K), lower than the static air (0.024 W / (m · K)) thermal conductivity than the corresponding inorganic Insulation material 2-3 orders of magnitude lower.        The thermal conductivity is 0.043 W / (m · K) even at a high temperature of 800 ° C. High temperature does not decompose,

Preparation and Classification of Dry Aerogel Particles

图片
Aerogel Particles, English aerogel, also known as xerogel. When the gel is stripped of most of the solvent, the content of the liquid in the gel is much less than the solid content, or the medium filled in the spatial network of the gel is a gas which is solid in appearance, which is the xerogel and Called Aerogel Particles. China Insulation --Tradematt  talk about the classification of Aerogel Particles and SiO2 Aerogel Particles preparation. Aerogel Particles can be divided into single-component Aerogel Particles, such as SiO2, Al2O3, TiO2, carbon Aerogel Particles (carbonized by organic Aerogel Particles) Al2O3, SiO2 / TiO2 and the like. The most typical and most studied aerogels are the one-component SiO2 aerogels and the aerogels (organic aerogels). At present, the preparation methods of SiO2 Aerogel Particles mainly include two modes of supercritical drying and atmospheric drying.        1, supercritical drying        The properties of SiO2 aerogels prepared by sup

External wall insulation materials construction matters needing attention

Exterior insulation materials in modern building energy conservation is crucial, external insulation materials construction should consider what the problem? 1. The durability of exterior insulation system should meet the requirements. Under normal conditions of use and maintenance, the service life of the external insulation shall not be less than 25 years. 2. System and the primary wall should be a reliable fixed. High-rise buildings should withstand large wind loads, and wall parts will have a lot of negative wind pressure (suction). Therefore, the insulation layer and the grassroots (inorganic materials) have a reliable bond, especially the use of (organic materials) insulation board, we must pay attention to this link. The insulation layer is made of inorganic material. 3. Exterior wall insulation system fire performance should be consistent with relevant state laws and regulations. Now used for high-rise building insulation more use of flame-retardant polystyrene board, such

China's External Wall Insulation Classification Fire Rating

China's External Wall Insulation Classification Fire Rating First, China's national standard GB8624-97 burning properties of building materials will be divided into the following categories: Class A: Non-flammable Building materials: Materials that hardly burn. B1 level: flame retardant Building materials: flame retardant materials have a good flame retardant. In the event of fire in the air or under the action of high temperature, it is hard to catch fire and it is not easy to spread quickly. When the source of ignition is removed, the combustion stops immediately. B2 level: Flammability Building materials: Flammable materials have a certain flame retardant effect. In the air in the event of fire or under the action of high temperature will immediately start burning, easily lead to the spread of fire, such as wooden posts, wooden truss, wooden beams, wooden stairs. B3 level: Flammability Building materials: no flame retardant effect, extremely easy to burn, fire risk