Silicone oil is a kind of chain like polyorganosiloxane with different degree of polymerization. It is made of dimethyldichlorosilane hydrolyzed with water to get primary polycondensation ring. The ring is cracked and rectified to get low ring. Then the ring, head sealing agent and catalyst are put together for polycondensation to get various mixtures with different degrees of polymerization. After the low boiling substance is removed by vacuum distillation, silicone oil can be made.

The most commonly used silicone oil, organic groups are all methyl, called methyl silicone oil. The organic group can also use other organic groups to replace some methyl groups, so as to improve the properties of silicone oil and apply to various uses. Other common groups are hydrogen, ethyl, phenyl, chlorophenyl, trifluoropropyl, etc. In recent years, organic modified silicone oil has developed rapidly, and many organic modified silicone oils with special properties have appeared.

Silicone oil is generally colorless (or light yellow), tasteless, non-toxic, non-volatile liquid. Silicone oil is insoluble in water, methanol, diol and - ethoxyethanol. It is miscible with benzene, dimethyl ether, methyl ethyl ketone, carbon tetrachloride or kerosene. It is slightly soluble in acetone, dioxane, ethanol and methanol. It has low vapor pressure, high flash point and ignition point, and low freezing point. With the different number of chain segments n, the molecular weight increases and the viscosity also increases. The solid silicone oil can have various viscosities, from 0.65% to millions of%. If you want to get low viscosity silicone oil, you can use acid clay as catalyst and adjust the polymerization at 180 ℃, or sulfuric acid as catalyst and adjust the polymerization at low temperature to produce high viscosity silicone oil or viscous substance. You can use alkaline catalyst.According to the chemical structure, silicone oil can be 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 trifluoropropyl silicone oil, methyl vinyl silicone oil, methyl hydroxy silicone oil, ethyl hydrogen silicone oil, hydroxy hydrogen silicone oil, cyano silicone oil, etc.; according to the use, there are damping silicone oil, diffusion pump silicone oil, etc Oil, hydraulic oil, insulating oil, heat transfer oil, brake oil, etc.

Silicone oil has excellent heat resistance, electrical insulation, weather resistance, hydrophobicity, physiological inertia and small surface tension. In addition, it also has low viscosity temperature coefficient and high compression resistance.