Used as a coupling agent in composite materials to improve adhesion between organic polymers and inorganic surfaces. Enhances water repellency and durability in coatings, especially on glass, metals, and concrete. Commonly applied in sealants and adhesives to boost performance under humid conditions. Also utilized in the treatment of fillers and pigments for plastics and rubber, improving dispersion and mechanical properties. Provides a hydrophobic surface layer in construction materials, reducing moisture absorption and increasing longevity.