Product Name: N-Octadecyltriethoxysilane
Chemical Formula: C30H64O3Si
CAS Number: 18456-74-3
Synonyms: Triethoxy(octadecyl)silane, n-Octadecyltriethoxysilane
Recommended Use: Coupling agent for fillers, surface treating in plastics/rubbers, hydrophobic coatings
Restrictions on Use: Intended only for industrial and research purposes; not for food, drug, or household use
Manufacturer Details: Standard supplier information will usually list address, emergency contact phone, and business hours support
Classification: Flammable liquids (Category 3), Skin irritation (Category 2), Eye irritation (Category 2A)
Signal Word: Warning
Hazard Statements: Causes skin irritation. Causes serious eye irritation. Flammable liquid and vapor. Harmful if inhaled or swallowed. Prolonged exposure can lead to organ effects, including potential neurotoxicity and effects on the respiratory system.
Pictograms: Flame, Exclamation mark
Precautionary Statements: Avoid breathing vapors. Use only with adequate ventilation. Wear appropriate gloves, eye/face protection, and clothing. Keep away from heat/open flame. Store in a cool, well-ventilated place, tightly closed.
Chemical Name: N-Octadecyltriethoxysilane
CAS Number: 18456-74-3
Content (w/w): 98–100%
Impurities: Less than 1% total for trace siloxanes, alkoxy byproducts
Additives: Product may contain minor stabilizing agents or inhibitors below 0.2% to extend shelf life or resist combustion, though these are typically proprietary and not considered hazardous
Inhalation: Remove person to fresh air promptly. Loosen tight clothing. Seek medical attention if symptoms persist. Watch for signs of respiratory distress like cough, headache, dizziness, or shortness of breath.
Skin Contact: Remove contaminated clothing immediately. Wash skin with soap and plenty of water for at least 15 minutes. If irritation, redness, or blistering occurs, seek medical attention.
Eye Contact: Rinse eyes for at least 15 minutes using water, holding eyelids apart. Remove contact lenses if present and easy to do. Get medical attention promptly if discomfort continues.
Ingestion: Rinse mouth with water. Do not induce vomiting. Never give anything by mouth to an unconscious person. Call medical help or local poison control right away.
Suitable Extinguishing Media: Foam, carbon dioxide, dry chemical powder; avoid using water except to cool containers
Hazards from Combustion: Vapors may form explosive mixtures with air and will drift along the ground, posing fire or flashback risk. May generate toxic gases, including silicon oxides, carbon oxides, and incompletely burned hydrocarbons.
Firefighting Instructions: Evacuate area of unprotected personnel. Use self-contained breathing apparatus and full protective gear. Approach from upwind and avoid breathing vapors.
Additional Advice: If container is exposed to fire, cool it with water spray from a safe distance. Remove containers from fire area if it can be done without risk.
Personal Precautions: Wear appropriate personal protective equipment, including gloves and goggles. Ventilate affected area. Eliminate all sources of ignition.
Environmental Precautions: Prevent entry to sewers, drains, and waterways. Notify authorities if significant spill enters the environment.
Methods for Containment: Dike or absorb spilled material using inert material like sand, earth, or vermiculite. Place in proper waste disposal containers.
Cleanup Procedures: Collect and dispose following local regulations. Wash spill site after material pickup is complete. Avoid breathing vapor or dust during cleanup.
Safe Handling: Avoid contact with skin, eyes, and clothing. Use only in well-ventilated areas or outdoors. Use spark-proof equipment. Do not breathe vapor, mist, or spray. Wash hands thoroughly after use.
Storage Requirements: Store in tightly closed containers in a cool, dry, well-ventilated place away from sources of ignition, heat, and incompatible substances. Keep away from moisture and acids. Segregate from oxidizers, strong bases, and acids.
Storage Class: Flammable liquids
Other Considerations: Keep locked up and out of reach of children. Regularly check storage containers for leaks or deterioration. Label containers clearly.
Exposure Limits: No established OSHA or ACGIH exposure limits; minimize exposure as a prudent industrial hygiene practice
Engineering Controls: Use process enclosures, local exhaust ventilation, or other engineering controls to keep airborne levels below recommended exposure limits.
Personal Protective Equipment (PPE): Wear impervious gloves (nitrile, neoprene recommended), chemical splash goggles or safety glasses, flame-resistant lab coat or apron. In poorly ventilated areas, use a NIOSH-approved organic vapor respirator.
Hygiene Measures: Wash hands, face, and exposed skin thoroughly after handling. Do not eat, drink, or smoke while using this chemical.
Appearance: Clear to slightly hazy colorless liquid; may appear yellowish on long storage
Odor: Mild, ether-like
Odor Threshold: Not available
pH: Not applicable (neat compound)
Melting Point/Freezing Point: Below -40°C
Boiling Point/Range: 192°C–206°C at 760 mmHg
Flash Point: About 93°C (closed cup)
Evaporation Rate: Not available
Flammability (solid, gas): Not applicable
Explosion Limits: Not determined
Vapor Pressure: 0.1 mmHg at 25°C
Vapor Density: >1 (air = 1)
Relative Density: Approximately 0.88–0.90 (water = 1)
Solubility: Poorly soluble in water; hydrolyzes on prolonged contact
Partition Coefficient (n-octanol/water): Log Kow estimated > 8
Autoignition Temperature: Above 290°C
Decomposition Temperature: Above 290°C
Viscosity: 3–5 cSt at 25°C, mostly non-viscous
Chemical Stability: Stable under recommended storage conditions. Can hydrolyze slowly on contact with moisture, producing ethanol.
Potentially Hazardous Reactions: Will react with water, acids, and bases, especially at elevated temperature. Release of flammable ethanol possible during hydrolysis.
Conditions to Avoid: Heat, flame, spark, ignition sources; exposure to moisture during storage.
Incompatible Materials: Strong oxidizing agents, acids, alkalis, moisture.
Hazardous Decomposition Products: Produces silicon oxides, carbon oxides, ethanol, and potentially other toxic gases in fire.
Likely Routes of Exposure: Inhalation, skin contact, eye contact, ingestion
Acute Toxicity: Expected to cause moderate irritation to skin and eyes. Possible drowsiness, headache, or dizziness with high vapor concentrations. Estimated low oral toxicity (LD50, rat): >2000 mg/kg.
Skin Corrosion/Irritation: Causes skin irritation with dryness, cracking, possible redness or burn after extensive contact.
Serious Eye Damage/Irritation: Causes irritation, tearing, redness, and possible injury on direct contact.
Respiratory Sensitization: Not considered a respiratory sensitizer, but vapor and aerosol can moderately irritate nose, throat, and lungs.
Chronic Effects: No conclusive human study data for carcinogenicity, mutagenicity, or reproductive toxicity. Repeated or long-term exposure may aggravate dermatitis and other pre-existing skin conditions.
Other Health Effects: Inhalation of decomposition products during fire may lead to more severe health risks.
Environmental Fate: Poorly soluble in water; hydrolyzes over time to silanols and ethanol
Mobility in Soil: Moderate to strong adsorption expected due to high log Kow; mostly adheres to soils and sediments
Persistence and Degradability: Hydrolyzes in moist environments to form stable silicon-containing products and ethanol, which are further biodegradable
Bioaccumulation Potential: High log Kow suggests potential to bioaccumulate, though hydrolysis products may not partition the same way
Aquatic Toxicity: Data limited; estimated as slightly to moderately toxic to aquatic life. Do not intentionally discharge into lakes, streams, or sewers.
Other Information: Avoid environmental release; compound not classified as persistent, bioaccumulative, and toxic (PBT) by major authorities but handle with care to minimize impact
Product Disposal: Dispose of according to local, regional, or national requirements. Incineration preferred in chemical incinerator equipped with afterburner and scrubber.
Contaminated Packaging Disposal: Triple rinse empty containers before disposal; offer for recycling where possible. Treat rinsate as hazardous waste.
Additional Notes: Do not dump into sewers, on the ground, or into any body of water. Consult a licensed waste disposal service for recommendations.
UN Number: UN1993
Proper Shipping Name: Flammable liquid, n.o.s. (contains N-Octadecyltriethoxysilane)
Transport Hazard Class: 3
Packing Group: III
Labels Required: Flammable liquid
Special Precautions: Protect containers from physical damage. Secure tightly to avoid leakage during transit. Maintain storage temperature below the flash point to avoid hazardous conditions. Follow all applicable transport regulations whether by land, air, or sea.
Inventory Status: Listed on TSCA, EINECS/ELINCS, DSL/NDSL, and other chemical inventories
OSHA: Classified as hazardous
SARA Title III: Not listed as a hazardous substance under Sections 302, 304, or 313
CERCLA: Not subject to CERCLA reporting requirements
California Proposition 65: No chemicals in this material known to the State of California to cause cancer, birth defects, or other reproductive harm
WHMIS Classification (Canada): B3 (Combustible liquid), D2B (Toxic materials causing other chronic effects)
Other Regulatory Notes: Product safety, health, and environmental regulations may differ in other countries, so check for compliance with national, regional, and local regulations before transport or disposal.
