Siloksaner

Siloksaner, or siloxanes, are a broad class of organosilicon compounds characterized by alternating silicon–oxygen bonds (Si–O–Si) with organic groups attached to silicon. The Si–O–Si backbone can form linear chains or cyclic rings, and the organic substituents (commonly methyl, ethyl, or phenyl groups) influence physical properties such as volatility, polarity, and flexibility.

In linear siloxanes, the repeating unit is often described as [R2SiO], yielding polymers such as polydimethylsiloxane (PDMS), a widely used silicone oil. Cyclic siloxanes consist of closed rings with the general formula [SiO]n and include common industrial and cosmetic ingredients. The diversity of substituents and chain architecture gives siloxanes a wide range of viscosities, volatilities, and mechanical properties, from liquids to elastomeric solids.

Production and processing typically involve hydrolysis and condensation of chlorosilanes or polymerization of siloxane monomers, with control over molecular weight and crosslinking to tailor end-use properties. Siloxanes are valued for thermal stability, low surface energy, chemical inertness, and excellent dielectric and lubricating properties. They are widely used in lubricants, sealants, elastomeric rubbers, cosmetics, medical devices, and electronic potting compounds, as well as in coatings and coatings additives.

Safety and environmental aspects vary by specific siloxane. Many linear siloxanes show low acute toxicity, but certain cyclic siloxanes have faced regulatory scrutiny due to concerns about environmental persistence and potential bioaccumulation. Regulatory reviews and exposure controls guide handling, use, and disposal of siloxane-containing products.