Hexadecyltrimethoxysilane

Hexadecyltrimethoxysilane (CAS 16415-12-6), also known as Cetyl trimethoxysilane, is a long-chain alkylsilane used to chemically modify inorganic surfaces and impart hydrophobicity. It bonds covalently to mineral substrates, enabling durable water repellency and improved compatibility between inorganic fillers and organic matrices. In coatings and sealants, it treats mineral fillers.

Commonly treated fillers include silica, calcium carbonate, and talc to improve dispersion and reduce moisture uptake in the final formulation. Adhesive and elastomer manufacturers use it as a coupling agent. This silane strengthens the interface between polymer matrices and glass or silica-based reinforcements. In plastics compounding, surface-treated fillers processed with this silane deliver better mechanical performance.

The material also helps in reducing agglomeration during processing. Personal care formulators apply it to powder pigments and mineral actives to convert hydrophilic surfaces to hydrophobic ones. This application improves skin feel and water resistance in color cosmetics. The product is supplied as a clear to slightly yellow liquid and is available in technical grade with purity levels at 95% or higher.

Packaging ranges from small drums to bulk IBC containers, depending on supplier and volume requirements. This versatile chemical ensures high performance across various industrial and consumer applications.