Octadecyltrimethoxysilane

Octadecyltrimethoxysilane (ODTMS) is a type of organosilane that is commonly used in the field of material science and nanotechnology. It is a long-chain alkylsilane with the chemical formula C18H39Si(OCH3)3.

Structure and Properties

Octadecyltrimethoxysilane is a colorless liquid at room temperature. It has a molecular weight of 390.67 g/mol. The molecule consists of an silicon atom bonded to three methoxy groups and one octadecyl group. The octadecyl group is a long hydrocarbon chain, which gives the molecule its hydrophobic properties.

Synthesis

Octadecyltrimethoxysilane can be synthesized through the reaction of chlorotrimethoxysilane with octadecene in the presence of a catalyst, such as platinum on carbon. The reaction is typically carried out under inert atmosphere to prevent oxidation.

Applications

Octadecyltrimethoxysilane is widely used as a surface modifier in the field of material science and nanotechnology. It can form a self-assembled monolayer (SAM) on a variety of surfaces, including metal, glass, and polymer surfaces. The resulting SAM is hydrophobic, which can be used to control the wettability of the surface.

In addition, octadecyltrimethoxysilane is also used as a precursor for the synthesis of silica nanoparticles. The long alkyl chain can act as a stabilizer, preventing the nanoparticles from agglomerating.

Safety

Like other organosilanes, octadecyltrimethoxysilane is flammable and should be handled with care. It can cause skin and eye irritation, and may be harmful if inhaled or swallowed.

See Also

• Organosilane
• Surface modifier
• Self-assembled monolayer