(3-Aminopropyl)triethoxysilane

(3-Aminopropyl)triethoxysilane (CAS 919-30-2), abbreviated APTES, is an aminosilane coupling agent that bridges inorganic surfaces and organic polymer matrices.

Where is (3-Aminopropyl)triethoxysilane used?

• Composites and rubber: surface treatment of glass fibers and silica, improving mechanical strength and moisture resistance
• Adhesives and sealants: coupling agent and adhesion promoter for bonding to metal or glass
• Electronics: functionalizes silicon wafers, sensor surfaces and PCB substrates for controlled deposition of coatings or bioactive layers
• Coatings: improves adhesion of primers and topcoats to aluminum and treated plastics
• It bonds to glass, metals and mineral fillers while presenting reactive amine groups toward resins, adhesives and coatings.

Good to know: No standard food or pharmacopeial grades apply; procurement specifications typically reference purity, amine content and hydrolysis stability.

Commercial specifications

• 98–99% purity for technical and research-grade applications
• Packaging from small laboratory quantities up to bulk drums