AMINOPROPYL TRIETHOXYSILANE- ▸ Coupling agent: Bonds inorganic substrates to organic resins.
- ▸ Glass-fiber sizing: Surface treatment for reinforced laminates.
- ▸ Adhesion promoter: Improves adhesive and sealant bonding.
- ▸ Foundry resins: Binder additive for sand-mold systems.
- ▸ Surface functionalization: Amine grafting onto silica and metal-oxide surfaces.
A grade-specific Safety Data Sheet (SDS) — with the complete hazard classification, handling precautions, and transport information — is supplied with every shipment and available on request. Confirm all safety and regulatory details against the SDS for your specific grade.
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Transport classification per the UN Model Regulations / 49 CFR 172.101 Hazardous Materials Table. Confirm against the grade-specific SDS (Section 14) before shipping.
3-Aminopropyltriethoxysilane (CAS 919-30-2), or APTES, is an amino-functional ethoxysilane coupling agent. It bonds inorganic surfaces such as glass, silica, metals, and mineral fillers to organic polymers, and is widely used to size glass fibers and as an adhesion promoter in adhesives, sealants, foundry resins, and coatings.
Frequently Asked Questions
What is APTES used for?
APTES (3-aminopropyltriethoxysilane, CAS 919-30-2, C9H23NO3Si) is an amino-functional ethoxysilane coupling agent. It bonds inorganic surfaces such as glass, silica, metals, and mineral fillers to organic polymers, and is widely used to size glass fibers and as an adhesion promoter in adhesives, sealants, foundry resins, and coatings, as well as for amine surface functionalization. RawSource supplies it in bulk.
Is aminopropyltriethoxysilane water soluble?
APTES is an alkoxysilane that reacts with water: the amino group makes it miscible with and reactive in aqueous systems, where the ethoxy groups hydrolyze to silanols and release ethanol. It is generally used in alcohol/water or anhydrous media; behavior depends on concentration and pH, so confirm conditions against the product data sheet.
Is APTES the same as APTMS?
No. APTES is the triethoxy aminosilane (CAS 919-30-2) and APTMS is the trimethoxy version (CAS 13822-56-5). They share the aminopropyl group but hydrolyze at different rates and release ethanol versus methanol respectively. Confirm identity by CAS number on the CoA.
What is the cost of bulk APTES?
APTES pricing is volume- and grade-dependent, so we do not publish a fixed price. Send your target quantity, grade, and packaging (drums, totes, or IBCs) for a current bulk quote; CoA and SDS accompany each shipment.
What CAS number and HS code apply to APTES?
The CAS number is 919-30-2 and it classifies under HS 2931.90 (organo-inorganic compounds, other). As an ethoxysilane it is moisture-sensitive; confirm packaging and the destination tariff line when ordering.