Silicone oil, also known as polysiloxane oil, is an organic silicon compound that remains liquid at room temperature. It primarily consists of silicon and oxygen atoms bonded covalently to form a long-chain structure. Organic groups such as methyl, ethyl, or benzyl are introduced at the ends or along the chains to enhance its properties. Thanks to its unique chemical structure and exceptional physicochemical properties, silicone oil is widely used across various industries. Typically, it is colorless (or light yellow), odorless, non-toxic, and exhibits low volatility, with outstanding chemical stability, heat resistance, electrical insulation, weather resistance, hydrophobicity, and low surface tension.

The development of silicone oil dates back to the 1940s. Initially, researchers experimented with dimethyl dichlorosilane to impregnate fabrics for waterproofing. In 1945, researchers at General Electric (GE) in the U.S. discovered that by impregnating fibers with sodium methylsiliconate in an alkaline solution and heating them, the fibers gained impressive waterproof qualities. This discovery laid the foundation for further research and applications of silicone oil.

In the early 1950s, Dow Corning, a leading U.S. company, found that treating fabrics with polysiloxanes containing Si-H structures not only improved waterproofing but also enhanced breathability. However, early silicone products faced issues such as poor tactile quality, brittle films, and peeling. To address these problems, researchers combined these polysiloxanes with polydimethylsiloxane (PDMS), significantly improving fabric flexibility and durability. As technology progressed, silicone oil products became more diverse, with enhanced performance and broader applications.