Small molecules lead the revolution of building materials, self-cleaning innovation of nano glass
with the advent of the dust season in Beijing, many people began to worry about the surface cleaning problem of the new landmark building in Beijing, the National Grand Theater, which has just been put into use. The appearance of the oval transparent eggshell structure is very inconvenient if the traditional manual cleaning method is adopted. The window cleaning machine is installed at the top of the floor, and the "foothold" of the installation can not be found when the robot is used for cleaning. Cleaning the 6000 square meter glass exterior wall seems to be an "impossible" task in dusty weather
fortunately, the National Grand Theater has adopted a new type of nano self-cleaning glass, that is, a layer of nano titanium dioxide film is plated on the surface of traditional glass. Dust coverage can be avoided to the greatest extent. In rainy days, the stains on the outer surface of the glass curtain wall will fall off automatically. Now, this new nano material has been widely used in new large-scale buildings in Beijing, including the new tower of Beijing Capital Airport and Wukesong Gymnasium, one of the Olympic venues
show their talents in Beijing's landmark buildings
there is no difference between Nano coated glass and ordinary glass, but its surface has super hydrophilic properties. This feature enables water molecules to spread evenly on the glass surface and completely infiltrate the glass. Through sunlight, the ultraviolet rays in the sunlight activate the nano materials in the coating on the glass surface to produce a photocatalytic reaction. The nano materials decompose the organic matter adsorbed to the glass surface due to pollution, decompose into water and carbon dioxide, and carry away the pollution attached to the glass through the gravity of water, so as to achieve a self-cleaning effect
its super hydrophilicity can prevent the formation of water droplets on the glass surface after rain, absorb the floating dust in the air, and form stubborn water marks. Compared with ordinary glass, rainwater can quickly "dry" without leaving "spots" after falling on nano self-cleaning glass. At the same time, the uniform water film formed by rainwater falling on the glass can easily send away the dirt on the surface
Zhang Heng, chief engineer of Beijing zhongkesena Glass Technology Co., Ltd., told, "Beijing's sandstorms and dry climate make it impossible to completely rely on rainwater for self-cleaning." However, the self-cleaning glass can be installed with an automatic spraying device with better mobility. PVC pipes are installed in the glass room for automatic flushing
subsequently, the Beijing Olympic project Wukesong Gymnasium, with a total area of 50000 square meters and an outer surface completely composed of glass curtain walls, also adopted nano glass
because of the hydrophilicity of nano glass, 7. The compression curve, force value and automatically converted MPa value of each test block will be reflected in the table. Water in the air cannot form droplets on the glass surface, so the glass surface will not fog. This feature is just applied to the new tower of terminal 3 of capital airport. In order to prevent glass fog from affecting navigation, all the peripheral glass of the tower adopts self-cleaning glass
combined with industrialization
in addition to the cleaning function, the nano coating has the characteristics of decomposing organic matter, which plays a role in killing bacteria and purifying the air. Tested by the Institute of physics and chemistry of the Chinese Academy of Sciences, the self-cleaning nano film has a strong decomposition effect on organic matter under sunlight and ultraviolet radiation, and has the functions of sterilization and mildew prevention, formaldehyde removal, odor removal, deodorization, and air environment treatment. At the same time, it is wear-resistant and weather resistant. According to the test report issued by the national building materials testing center, the glass film surface can withstand the erosion of general acid rain and alkaline substances. This property can also avoid the erosion of acid rain and alkali on glass
the biggest advantage of the industrialization of self-cleaning glass developed by Sina Glass Technology Co., Ltd. is that it can be produced offline. Zhang Heng said that the investment in establishing a new flat glass production line is at least tens of millions of yuan, and the research results of the Chinese Academy of Sciences can make this nano coating be sprayed on all kinds of glass offline under normal temperature and pressure, including Low-E glass and insulating glass, which are widely used now, and can be sprayed on all levels of Low-E glass according to user requirements
now, senna Glass Technology Co., Ltd. takes Beijing as an example and selects Yaohua Glass and new Jackie Chan as production bases for market promotion. At present, the selling price of nano self-cleaning glass is about 70-80 yuan per square meter, which is 30-50 yuan per square meter higher than that of ordinary glass. However, the import of similar foreign products into China is as high as 260 yuan. Zhang Heng explained that the main reason was that foreign nano glass could not be produced offline, and the original glass chips had to be imported from abroad, which led to a rise in prices
now, with the development of energy-saving market, all glass enterprises cooperating with Sena have been promoted in ordinary commercial projects. The Sheraton Hotel in Changchun and the Kaichen Plaza in Beijing have all adopted nano self-cleaning glass
the installation process is the bottleneck
although the nano glass of the National Grand Theater has a self-cleaning effect, the periphery was still manually cleaned before the opening of the two sessions. Zhang Heng said frankly that the self-cleaning effect of the National Grand Theater did not reach the effect of the experiment. Although the nano film has a certain hardness, strong scratching will damage it. After the completion, some construction personnel threw a large amount of waste materials from the glass surface, causing the scratch of the film. When using silica gel to install glass, the chemical materials on its surface are damaged due to improper methods
nano glass mainly relies on optical reaction, and its sales volume with nano biomedical materials market in China in 2015 has been nearly 144 billion yuan. The nano film has a chemical effect, and in principle, with the continuous occurrence of chemical reaction, its nano materials will continue to decrease. For this reason, SANA glass company has conducted a 10-year simulation of the relative strength, and the simulation effect has proved that there will be no substantial change. However, Zhang Heng frankly said that it is still uncertain how many years it can be used in 10 years
now, another innovation is in progress. In order to meet the energy-saving transformation needs of more existing buildings, Zhang Heng and his colleagues are studying how to spray nano films on the installed glass
at the same time, Zhang Heng said that nano films are not only applied to glass. In the next step, aluminum plates, marble and other building materials will become self-cleaning materials. Now, the Committee of Chairman Mao Memorial Hall has allocated a special fund for the Chinese Academy of Sciences to research and develop the use of nano materials on white marble
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