Silicone oil is a type of polydimethylsiloxane with chain like structures of different degrees of polymerization. The commonly used silicone oil, with all organic groups being methyl, is called methyl silicone oil. Organic groups can also replace some methyl groups with other organic groups to improve certain properties of silicone oil and make it suitable for various purposes. Common other functional groups include 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 emerged.

Silicone oil is generally a colorless (or pale yellow), odorless, non-toxic, and non-volatile liquid. Silicone oil is insoluble in water, methanol, diols, and ethoxyethanol. It is miscible with benzene, dimethyl ether, methyl ethyl ketone, carbon tetrachloride, or kerosene, and slightly soluble in acetone, dioxane, ethanol, and alcohols. It has a very low vapor pressure, high flash point and ignition point, and low freezing point. As the number of segments n varies, the molecular weight increases and the viscosity also increases. This silicone oil can have various viscosities.

Silicone oil can be classified by chemical structure into methyl silicone oil, ethyl silicone oil, phenyl silicone oil, methyl hydrogen containing silicone oil, methyl phenyl silicone oil, methyl chlorophenyl silicone oil, methyl ethoxy silicone oil, methyl trifluoropropyl silicone oil, methyl vinyl silicone oil, methyl hydroxyl silicone oil, ethyl hydrogen containing silicone oil, hydroxyl hydrogen containing silicone oil, cyanide containing silicone oil, etc; In terms of usage, there are damping silicone oil, diffusion pump silicone oil, hydraulic oil, insulation oil, heat transfer oil, brake oil, etc.

Silicone oil has excellent heat resistance, electrical insulation, weather resistance, hydrophobicity, physiological inertness, and low surface tension. In addition, it has a low viscosity temperature coefficient and high compression resistance. Some varieties also have radiation resistance. Among them, amino silicone oil and block silicone oil are widely used in the textile industry, especially block silicone oil, which has an increasingly prominent position in the current textile industry due to its excellent performance.