siliconates

Siliconates are a class of chemical compounds characterized by the presence of a silicon-oxygen (Si-O) bond within an anionic structure. These compounds can be considered derivatives of silicic acid where one or more hydroxyl groups are replaced by an oxygen atom bonded to another silicon atom, or by an organic radical. In their simplest form, siliconates are salts of silicic acid, often containing alkali metals like sodium or potassium.

The structure of siliconates varies. Monomeric siliconates are based on the orthosilicate anion, [SiO4]4-, where the silicon atom is tetrahedrally coordinated to four oxygen atoms. However, silicon readily forms extended structures, leading to polymeric siliconates. These polymers can feature linear, branched, or cyclic arrangements of silicon-oxygen tetrahedra. The nature of the counterion also plays a role in the properties and solubility of siliconates. Organic siliconates, also known as organosilicates, incorporate organic groups directly bonded to the silicon atom, alongside oxygen linkages.

Siliconates find applications in various fields. They are used as binders, in the formulation of coatings, and as precursors for ceramic materials. Their ability to form stable Si-O networks makes them valuable in high-temperature applications. In the context of construction, certain siliconates are employed as concrete densifiers and water repellents, penetrating the porous structure of concrete and reacting to form a denser, less permeable surface. The precise chemical structure and properties of a siliconate dictate its suitability for a specific industrial use.