The basic structural unit of silicone products is composed of silicon-oxygen links, and the side chains are connected to various other organic groups through silicon atoms. Therefore, the structure of the silicone product contains both "organic groups" and "inorganic structures". This special composition and molecular structure make it integrate the characteristics of organic matter and the function of inorganic matter. Compared with other polymer materials, the most outstanding properties of silicone products are:
Temperature resistance
Silicone products are based on silicon-oxygen (Si-O) bonds as the main chain structure. The C-C bond energy is 82.6 kcal / mole. The Si-O bond energy is 121 kcal. / Gram molecule, so the thermal stability of organic silicon products is high, the chemical bonds of molecules at high temperatures (or radiation exposure) do not break or decompose. Silicone is not only resistant to high temperatures but also to low temperatures and can be used over a wide temperature range. Whether it is chemical or physical mechanical properties, the change with temperature is small.
2. Weatherability
The main chain of silicone products is -Si-O-, and there is no double bond, so it is not easily decomposed by ultraviolet light and ozone. Silicone has better thermal stability and resistance to radiation and weather than other polymer materials. The service life of organic silicon in natural environment can reach decades.
3． Electrical insulation performance
Silicone products all 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 small. Therefore, they are a stable electrical insulation material and are widely used in the electronics and electrical industries. In addition to excellent heat resistance, silicones also have excellent water repellency, which is a guarantee of high reliability for electrical equipment in wet conditions.
4． Physiological inertia
Polysiloxanes are one of the least reactive compounds known. They are very resistant to biological aging, have no rejection reaction with the animal body, and have good anticoagulant properties.
5. Low surface tension and low surface energy
Silicone's main chain is very compliant, 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, small 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-adhesion, lubrication, glazing and other excellent properties.