Silicon is a chemical element. Its chemical symbol is Si. The silicon system has two allotropes: amorphous silicon and crystalline silicon. It belongs to the third period of the periodic table and belongs to the metal-like element of the IVA group. Silicon is also a very common element, but it rarely appears in nature as a simple substance, but in the form of complex silicate or silica, which is widely present in rocks, gravel, and dust.

       The reserves of silicon in the universe rank eighth. In the earth's crust, it is the second most abundant element, constituting 26.4% of the total mass of the earth's crust, second only to the first oxygen (49.4%).

       The origin of the name of silicon: English silicon, comes from the Latin silex, silicis, meaning flint (flint). In the early days of the Republic of China, scholars originally translated this element as "silicon" and pronounced it as "xi (you can read xi sound by the side of Gui)" (also, "silicon" is a variant of "砉", pronounced huo).

       However, in the time and space at that time, since the pinyin scheme has not been popularized, it is generally misread as gui. In addition to the original Chinese name, transliteration is often used for the translation of chemical elements. The Society of Chemistry noticed this problem and created the word "silicon" to avoid misreading. Taiwan still uses the word "silicon" to this day. In mainland China, in February 1953, the Chinese Academy of Sciences held a nationwide symposium on the naming of chemical substances. Some scholars adopted and announced the agreement on the grounds that "silicon" and other chemical elements "tin" and "selenium" are easily confused. Changed back to the original name "Si" and pronounced "gui", but did not realize that "Si" should also be pronounced xi.

       The content of silicon in the earth's crust is the largest element except oxygen. If carbon is the basis of all organic life, then silicon occupies the same place in the earth's crust, because the main part of the earth's crust is composed of silicon-containing rock layers. Almost all of these rocks are composed of silica and various silicates. Feldspar, mica, clay, olivine, hornblende, etc. are all silicates; crystal, agate, jasper, opal, quartz, sand, and flint are all silica.

       Silica gel is a kind of silicon material. According to its properties and components, silica gel can be divided into organic silica gel and inorganic silica gel. Inorganic silica gel is a highly active adsorption material, usually reacted with sodium silicate and sulfuric acid, and its chemical formula is mSiO2.nH2O. It is insoluble in water and any solvents, non-toxic, tasteless, chemically stable, and does not react with any substances except strong alkalis and hydrofluoric acid. Various types of silica gel constitute abnormal micro-pore planning due to abnormal manufacturing methods.

       The chemical composition and physical design of silica gel have decided that it has many characteristics that other similar materials cannot replace: high adsorption function, good thermal stability, stable chemical properties, and high mechanical strength. According to the size of its pore size, silica gel is divided into: macroporous silica gel, coarse pore silica gel, type B silica gel, and fine pore silica gel.

       According to its properties and components, silica gel can be divided into organic silica gel and inorganic silica gel. Inorganic silica gel is a highly active adsorption material, usually reacted with sodium silicate and sulfuric acid, and its chemical formula is mSiO2.nH2O. It is insoluble in water and any solvents, non-toxic and tasteless, chemically stable, and does not react with any substances except strong alkalis and hydrofluoric acid. Various types of silica gel constitute abnormal micropore planning due to abnormal manufacturing methods. The chemical composition and physical design of silica gel have decided that it has many characteristics that other similar materials cannot replace: high adsorption function, good thermal stability, stable chemical properties, and high mechanical strength.

       According to the size of its pore size, silica gel is divided into: macroporous silica gel, coarse pore silica gel, type B silica gel, and fine pore silica gel. The simple substance of silicon is artificially refined, and it is divided into two types: crystalline and amorphous. Crystalline silicon has a three-dimensional network structure similar to diamond. Therefore, it exhibits the physical properties of high hardness, high melting point, and brittle texture. In addition, silicon is a trapezoidal line with the periodic table, and its properties are between metal and non-metal. It is a gray-black semiconductor with metallic luster.

       Due to the unique structure of organic silicon, it combines the properties of inorganic and organic materials. It has basic properties such as low surface tension, low viscosity-temperature coefficient, high compressibility, and high gas permeability. It also has high and low temperature resistance, electrical insulation, and oxidation resistance. Excellent properties such as resistance, weather resistance, flame retardancy, water repellency, corrosion resistance, non-toxic and tasteless, and physiological inertia. It is widely used in aerospace, electronic and electrical, construction, transportation, chemical, textile, food, light industry, medical and other industries. Among them, silicone is mainly used in sealing, bonding, lubrication, coating, surface activity, demoulding, defoaming, foam suppression, waterproofing, moisture-proof, inert filling, etc. With the continuous growth of the number and variety of silicones, the application areas continue to expand, forming a unique and important product system in the field of new chemical materials. Many varieties are irreplaceable and indispensable for other chemicals.

       Excellent performance silicon organic compound. For example, silicone plastic is an excellent waterproof coating material. Spraying silicone on the walls of the subway can solve the water seepage problem once and for all. Coating a thin layer of silicone plastic on the surface of ancient cultural relics and sculptures can prevent moss from growing and resist wind, rain and weathering.

       Silicon is a very safe substance. It does not react by the immune system, nor will it be swallowed by cells, nor will it breed bacteria or react with chemicals. At the same time, there is also silica gel developed and produced for skin wounds. It is a very safe material to protect wounds, and it is approved by the health authorities of various countries.

       According to the chemical structure, silicone oil is divided into methyl silicone oil, ethyl silicone oil, phenyl silicone oil, methyl hydrogen silicone oil, methyl phenyl silicone oil, methyl chlorophenyl silicone oil, methyl ethoxy silicone oil, methyl trifluoropropane Base silicone oil, methyl vinyl silicone oil, methyl hydroxy silicone oil, ethyl hydrogen silicone oil, hydroxy hydrogen silicone oil, cyanide silicone oil, etc.; from the point of use, there are damping silicone oil, diffusion pump silicone oil, hydraulic oil, insulating oil, Heat transfer oil, brake oil, etc.

       Silicone oil has excellent heat resistance, electrical insulation, weather resistance, hydrophobicity, physiological inertness and small surface tension. In addition, it also has a low viscosity-temperature coefficient and high compression resistance) Some varieties also have radiation resistance Performance.