Trimethoxy(octadecyl)silane (OTMS) is an alkyl silane that functionalizes a variety of nanoparticle surfaces and facilitates a hydrophobic coating with a high-water contact angle and low surface energy.

Trimethoxy(octadecyl)silane (OTS) is an important alkylsilane that can form strong covalent bonds with silicon oxide and serves as a potential lubricant for micro electro mechanical systems (MEMS). OTS is largely used for surface chemical modification, modifying silica resulted in an increased charge carrier mobility for a variety of vacuum deposited and solution cast organic semiconductors.

Magnetic nanoparticles (Fe₂O₃) can be surface modified with OTMS. It forms a sorbent for the magnetic solid-phase extraction (MSPE) of endocrine disruptors (organochlorine pesticides) from milk samples. It may form a corrosion protective coating on AZ31 magnesium alloy that finds potential application in automotive industry. It may also be used to form a composite with fly ash that can be coated to achieve a superhydrophobic and UV-protected cotton fabric.

OTS is used for the development of self assembled monolayers(SAMs). OTS is also used to modify the silica dielectric surface in organic field effect transistors.