(3-Aminopropyl)triethoxysilane

CAS: 919-30-2

Overview

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

It bonds to glass, metals, and mineral fillers while presenting reactive amine groups toward resins, adhesives, and coatings, improving interfacial adhesion across composite systems.

In fiber-reinforced composites and filled rubber, APTES is applied as a surface treatment for glass fibers and silica, significantly improving mechanical strength and moisture resistance.

Epoxy adhesive and sealant formulators use it both as a coupling agent and adhesion promoter, particularly where bonding to metal or glass substrates is critical for the application.

In electronics, it functionalizes silicon wafers, sensor surfaces, and printed circuit board substrates to enable controlled deposition of coatings or bioactive layers for advanced devices.

Coatings producers incorporate it to improve adhesion of primers and topcoats to difficult substrates, including aluminum and treated plastics, ensuring long-term durability and performance.

APTES is supplied as a liquid, typically at 98–99% purity for technical and research-grade applications. It is available in packaging ranging from small laboratory quantities up to bulk drums.

No standard food or pharmacopeial grades apply; procurement specifications typically reference purity, amine content, and hydrolysis stability to ensure consistent chemical performance.

Physical Properties

Melting Point	-70 °C
Boiling Point	217 °C
Density	0.94 g/cm³ @ Temp: 25 °C
Flash Point	205 °F
Appearance	Colorless transparent liquid
Color	APHA: ≤25
Odor	Fishy odor
Form	Liquid
Water Solubility	REACTS
Vapor Pressure	0-7910Pa at 25℃
Refractive Index	n 20/D 1.422
pH	11 (20g/l, H2O, 20℃)
Log P	-4--0.3 at 20℃

Safety & Handling

Danger GHS05 GHS07 GHS08 Hazard Statements H302 Harmful if swallowed H314 Causes severe skin burns and eye damage H317 May cause an allergic skin reaction H318 Causes serious eye damage H335 May cause respiratory irritation H336 May cause drowsiness or dizziness H373 May causes damage to organs through prolonged or repeated exposure Precautionary Statements P260 Do not breathe dust/fume/gas/mist/vapours/spray. P261 Avoid breathing dust/fume/gas/mist/vapours/spray. P264 Wash … thoroughly after handling. P270 Do not eat, drink or smoke when using this product. P271 Use only outdoors or in a well-ventilated area. P272 Contaminated work clothing should not be allowed out of the workplace. P280 Wear protective gloves/protective clothing/eye protection/face protection. P316 Get emergency medical help immediately. P317 Get emergency medical help. P319 Get medical advice/attention if you feel unwell. P321 Specific treatment (see … on this label). P330 Rinse mouth. P363 Wash contaminated clothing before reuse. P405 Store locked up. P501 Dispose of contents/container in accordance with local regulations. P264+P265 Wash … thoroughly after handling. P301+P317 Get emergency medical help. P302+P352 IF ON SKIN: Wash with plenty of water. P304+P340 IF INHALED: Remove person to fresh air and keep comfortable for breathing. P333+P317 Get emergency medical help. P362+P364 Take off contaminated clothing and wash it before reuse. P403+P233 Store in a well-ventilated place. Keep container tightly closed. P301+P330+P331 Rinse mouth. Do NOT induce vomiting. P302+P361+P354 IF ON SKIN: Take off immediately all contaminated clothing. Rinse skin with water/shower. P305+P354+P338 IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing.

Trade & Regulatory

HS Code	29310095
UN Number	2735
ADR Class	8
Packing Group	II
Storage Class	8A - Combustible corrosive hazardous materials
WGK (Germany)	1

Other Names

Industries

Personal Care & Cosmetics Automotive Electronics Plastics & Polymers Coatings, Adhesives, Sealants & Elastomers