Potassium methylsiliconate

Potassium methylsiliconate (CAS 31795-24-1), also supplied under trade designations such as Wacker BS 15 and T 51, is an aqueous alkaline siliconate used to impart water repellency.

It provides surface protection across construction and industrial substrates. It functions by penetrating porous materials and forming a hydrophobic barrier upon reaction with carbon dioxide in the atmosphere.

In construction, it is applied to concrete, masonry, and brick to reduce water absorption and prevent efflorescence without altering surface appearance. This ensures long-term structural integrity.

Textile and paper manufacturers use it to confer durable water-repellent finishes on fibres and sheet materials. Leather treatment formulations incorporate it to improve moisture resistance while maintaining breathability.

In personal care, it appears in hair and skin preparations where surface-conditioning and water-repellent film formation are required. These applications benefit from its unique chemical properties.

Potassium methylsiliconate is supplied as an aqueous alkaline solution, typically at concentrations around 25–50% active content. This concentration allows for versatile dilution depending on the specific use case.

Technical grade is the predominant commercial form, suited for construction and industrial applications. Grades meeting cosmetic raw material standards are available for specialized personal care formulations.