1. Basic Product Profile

• Full IUPAC Name: 3-triethoxysilylpropan-1-amine
• Aliases: APTES, 3-(Triethoxysilyl)propylamine, γ-Aminopropyltriethoxysilane
• CAS Number: 919-30-2
• EINECS: 213-048-1
• Molecular Formula: C9H23NO3Si
• Molecular Weight: 221.37
• Chemical Classification: Amino-functional silane coupling agent, inorganic-organic interface modifier, surface treatment reagent, adhesive primer raw material
• Core Advantages
  Dual-functional silane molecule with reactive triethoxysilyl group and primary amino group. Alkoxy groups hydrolyze to bond with glass, silica, metal, mineral fillers; amino groups form chemical links with epoxy, polyurethane, acrylic, rubber polymers. Dramatically improves adhesion between inorganic fillers and organic resins, enhances composite mechanical strength, water resistance and weather resistance. Widely used in glass fiber sizing, mineral filler modification, coating primer, adhesive and electronic packaging industry.

2. Physical & Chemical Properties

2.1 Physical Index

1. Appearance: Colorless transparent low-viscosity liquid
2. Odor: Mild characteristic amine odor
3. Solubility: Miscible with ethanol, methanol, acetone, toluene; hydrolyzes and reacts with water; insoluble in long-chain alkanes
4. Boiling Point: 217–222 °C
5. Density (20℃): 0.945–0.955 g/cm3
6. Refractive Index nD20: 1.418–1.423
7. Flash Point: 96 °C
8. pH (hydrolyzed aqueous solution): Weakly alkaline
9. Hygroscopy: Hygroscopic, reacts rapidly with atmospheric moisture

2.2 Chemical Properties

1. Dual functional structure: Si(OCH2CH3)3 hydrolyzable group + terminal -NH2 primary amine group
2. Hydrolysis reaction: Ethoxy groups hydrolyze under water to generate silanol Si-OH, condense to form Si-O-Si bonds on inorganic surfaces
3. Amino reactivity: Primary amine undergoes ring-opening with epoxy, crosslinking with isocyanate, hydrogen bonding with polar polymer chains
4. Thermal stability: Stable below 180 ℃; prolonged heating above 220 ℃ triggers decomposition and silanol polycondensation
5. Water sensitivity: Must avoid long-term contact with water; aqueous working solution needs fresh preparation
6. Acid & Alkali Stability: Accelerated hydrolysis under acid/alkali catalysis; pure product stable in neutral airtight storage
7. Compatibility: Compatible with polar resins, alcohols, aromatic solvents; incompatible with strong acids, acyl chlorides, isocyanates in direct mixing

3. Main Application Fields

3.1 Composite Material Coupling Agent (Core Usage)

1. Glass fiber sizing agent for epoxy, PP, PA composite materials; boosts tensile strength and water resistance of fiber-reinforced plastics
2. Surface modifier for silica, talc, calcium carbonate, aluminum hydroxide mineral fillers, improves filler dispersion in rubber and plastic matrix

3.2 Coating & Adhesive Primer

1. Adhesion promoter for glass, metal, ceramic coatings; eliminates coating peeling and bubbling issues
2. Primer additive for structural adhesives, sealants, enhances bonding strength between inorganic substrates and organic glue

3.3 Electronic & Optical Materials

1. Surface treatment reagent for glass wafer, optical lens, quartz substrate to modify surface hydrophilicity
2. Packaging auxiliary for semiconductor epoxy molding compounds, improves interface bonding between chip and encapsulant

3.4 Biochemical & Analytical Reagent

4. Quality Specification Table