color-1
cas 3069-42-9

​Octadecyltrimethoxysilane

Chemical Name: Octadecyltrimethoxysilane
Product Category: Long-chain Silanes | Silane Coupling Agent
Structural Formula: 3069-42-9
CAS No.: 3069-42-9
EINECS: 221-332-4
Molecular Formula: C₂₁H₄₆O₃Si
Molecular Weight: 374.67 g/mol
Appearance: Colorless transparent liquid

​Octadecyltrimethoxysilane Description

Octadecyltrimethoxysilane (CAS 3069-42-9) also known as n-Octadecyltrimethoxysilane, is an organosilicon compound widely used in various industrial applications due to its ability to modify surface properties, rendering surfaces hydrophobic and enhancing compatibility between inorganic materials and organic polymers.

Chemical NameOctadecyltrimethoxysilane
Synonymsn-Octadecyltrimethoxysilane, Stearyltrimethoxysilane, Trimethoxyoctadecylsilane
Boiling Point170°C at 0.1 mmHg
Density0.883 g/mL at 25°C
Flash Point284°F (140°C)
Refractive Index (n²⁰/D)1.439
SolubilitySlightly soluble in chloroform; hydrolyzes slowly in the presence of moisture
Uses
  • Surface Modification: Enhances the compatibility of inorganic materials (glass, silica, alumina, etc.) with polymers, improving strength, durability, and water resistance.

  • Hydrophobic Coatings & SAMs: Converts hydrophilic surfaces into water-repellent ones, widely used in nanotechnology and analytical chemistry.

  • Anti-Fog Optical Coatings: Prevents fogging on glass and optical surfaces, ensuring clear visibility in eyewear, automotive glass, and optics.

  • Protection of Artifacts & Structures: Shields historical relics and outdoor structures from water damage, corrosion, and weathering.

Safety and Handling
  • Hazard Classification: Irritant (Xi)
  • Risk Phrases: R36/37/38 – Irritating to eyes, respiratory system, and skin
  • Safety Phrases: S26 – In case of contact with eyes, rinse immediately with plenty of water and seek medical advice; S36 – Wear suitable protective clothing
Packaging
  • Our standard packing is net 25kg / 200 kg drums / 1000kg/IBC,or according to your requirements.
Sample
  • Provided for free
Inventory items
  • 6 tons
Price

Packaging Specifications

Packaging Specifications

Get the Latest Pricing and Information

  • Quick and helpful reply within 8 hours;
  • Tailored solutions provided for your project;
  • One-stop purchasing service.
Please enable JavaScript in your browser to complete this form.

​Octadecyltrimethoxysilane: Guide

Octadecyltrimethoxysilane (OTMS), is an organosilicon compound widely used for surface modification, hydrophobic coatings, and self-assembled monolayers. It plays a crucial role in nanotechnology, material science, and advanced coatings.

Safety & Handling
OTMS may cause skin and eye irritation. Use protective gloves and goggles when handling to avoid direct contact. Store in a cool, dry place away from moisture to prevent hydrolysis.

Conclusion
OTMS is a high-performance silane compound with significant applications in hydrophobic coatings, antimicrobial surfaces, and fire-resistant materials, making it an essential material in various industrial fields.

Scroll to Top