organosilicate

Organosilicates are a broad class of organosilicon compounds in which silicon carries organic substituents and is linked to oxygen, forming Si–O–R or Si–O–Si bonds. They lie at the intersection of organic chemistry and silicon–oxygen chemistry and are commonly described as silicon-centered derivatives that include carbon-based groups such as alkyl or aryl moieties.

Most widely studied organosilicates are alkoxysilanes, e.g., methyltrimethoxysilane (MTMS), phenyltrimethoxysilane (PTMS), and vinyltrimethoxysilane (VTMS). These compounds contain at least one Si–C bond and several Si–O–R groups. They are typically colorless liquids or low-melting solids and are precursors in the sol-gel process, where hydrolysis and polycondensation convert them into siloxane networks (Si–O–Si) that form gels, coatings, or porous materials. Their organic substituents influence reactivity, hydrophobicity, and compatibility with organic polymers.

Preparation of organosilicates usually involves formation of Si–OR bonds from chlorosilanes or hydrosilylation routes followed by alkoxide substitution, or hydrolysis of silane derivatives under controlled conditions. Handling often requires moisture sensitivity because hydrolysis is intrinsic to their reactivity.

Applications are broad: surface modification and coupling agents in composites, coatings and sealants, precursors for silica-based ceramics and aerogels, and components in electronics and optics. As catalysts supports and in functional coatings, organosilicates enable controlled crosslinking and tuning of material properties through the choice of organic substituents and alkoxy groups.