The basic structural unit of organic silicone products is composed of silicon-oxygen chain links, and the side chains are connected to various other organic groups through silicon atoms.
This special composition and molecular structure make it integrate the characteristics of organic substances and the functions of inorganic substances. Compared with other polymer materials, the most outstanding properties of silicone products are:
1.Temperature resistance
Silicone products are based on the silicon-oxygen (Si-O) bond as the main chain structure. The bond energy of the C-C bond is 82.6 kcal/mole. The bond energy of the Si-O bond is 121 kcal in the silicone /Mole, so the thermal stability of organic silicone products is high, and the chemical bonds of molecules will not be broken or decomposed under high temperature (or radiation exposure). Silicone is not only resistant to high temperatures, but also resistant to low temperatures, and can be used in a wide temperature range. Whether it is chemical properties or physical mechanical properties, it is less affected by temperature.
2. Weather resistance
The main chain of silicone products is -Si-O-, there is no double bond, so it is not easy to be decomposed by ultraviolet light and ozone. Silicone has better thermal stability, radiation resistance and weather resistance than other polymer materials. The life span of organic silicone can reach several decades in natural environment.
3. Electrical insulation performance
Silicone products have good electrical insulation properties. Their dielectric loss, voltage resistance, arc resistance, corona resistance, volume resistivity and surface resistivity are among the best in insulating materials, and their electrical properties are affected by temperature and frequency. The impact is very small. Therefore, they are a kind of stable electrical insulating materials, which are widely used in the electronics and electrical industries. In addition to excellent heat resistance, silicone also has excellent water repellency, which is a guarantee for high reliability of electrical equipment used in wet conditions.
4. Inert material
“Polysiloxane compounds are one of the most innert compounds known.” They are resistant to biological aging, have no rejection reaction with animal bodies, and have good anticoagulant properties.
5. Low surface tension and low surface energy
The main chain of organosilicon is very flexible, and its intermolecular force is much weaker than that of hydrocarbons. Therefore, it has lower viscosity than hydrocarbons of the same molecular weight, weak surface tension, low surface energy, and strong film-forming ability. This low surface tension and low surface energy are the main reasons for its many applications: hydrophobicity, defoaming, foam stability, anti-sticking, lubrication, glazing and other excellent properties.
The application of silicone
Since silicone has the above-mentioned excellent properties, its application range is very wide. It is not only used as a special material for aviation, cutting-edge technology, and military technology, but also used in various sectors of the national economy. Its application range has been expanded to: construction, electronics and electrical, textiles, automobiles, machinery, leather and paper, chemical and light industry, Metal and paint, medicine and medical treatment, etc.