Product Name: Methyltrimethoxysilane
Chemical Formula: C4H12O3Si
Synonyms: Trimethoxy(methyl)silane, MTMS
CAS Number: 1185-55-3
Recommended Use: Chemical intermediate, adhesion promoter, surface modifier
Supplier/Manufacturer Details: Contact information for the supplier, including phone number, physical address, and emergency telephone number.
Classification: Flammable Liquid (Category 3), Serious Eye Irritation (Category 2A), Skin Irritation (Category 2)
Label Elements: Flame, Exclamation mark
Signal Word: Warning
Hazard Statements: Highly flammable liquid and vapor. Causes skin and eye irritation. May cause respiratory irritation.
Precautionary Statements: Keep away from heat, sparks, open flames. Use explosion-proof electrical equipment. Avoid breathing vapors or mists. Wash hands after handling. Wear protective gloves, clothing, and eye protection.
Component: Methyltrimethoxysilane
CAS No.: 1185-55-3
Concentration: ≥ 98%
Impurities: Methanol may be released during hydrolysis
Additives: No significant additives present
Inhalation: Move person to fresh air. If symptoms develop, seek medical attention. Provide artificial respiration if necessary.
Skin Contact: Remove contaminated clothing. Wash affected area with soap and water. If irritation persists, get medical advice.
Eye Contact: Rinse cautiously with water for several minutes. Remove contact lenses if present and continue rinsing. Seek medical attention if irritation persists.
Ingestion: Rinse mouth, do not induce vomiting. Seek immediate medical attention. Never give anything by mouth to an unconscious person.
Suitable Extinguishing Media: Alcohol-resistant foam, dry chemical, carbon dioxide, water spray
Unsuitable Extinguishing Media: Direct water jet can spread fire
Specific Hazards: Vapors may form explosive mixtures with air. Containers may rupture from pressure build-up when exposed to extreme heat. Hazardous combustion products include carbon oxides and silicon oxides.
Special Protective Equipment: Firefighters need self-contained breathing apparatus and full protective clothing.
Firefighting Instructions: Evacuate area, use water spray to cool adjacent containers, prevent runoff from entering drains.
Personal Precautions: Remove ignition sources, ventilate area, use personal protective equipment including gloves, goggles, and protective clothing.
Environmental Precautions: Prevent entry into sewers, drains, or watercourses. Notify authorities in case of large spills.
Methods for Containment and Clean-Up: Absorb with inert material such as sand or earth, collect into suitable containers for disposal. Use non-sparking tools. Wash spill area with water after material pick-up is complete.
Handling: Use only in well-ventilated areas. Avoid contact with skin, eyes, and clothing. Do not breathe vapors or spray. Take measures to prevent static discharge. Use grounding and bonding for transfers.
Storage: Store in tightly closed, properly labelled containers away from heat, open flames, and direct sunlight. Keep in a cool, dry, and well-ventilated area. Keep away from incompatible materials like strong oxidizers, acids, and bases.
Occupational Exposure Limits: TLV not established for Methyltrimethoxysilane. Possible exposure to methanol (TWA 200 ppm, STEL 250 ppm).
Engineering Controls: Use local exhaust ventilation, process enclosure, or other engineering controls to limit airborne exposure.
Personal Protection: Wear protective gloves impervious to chemicals, chemical safety goggles, lab coat, and use a respirator if ventilation is inadequate. Ensure eyewash stations and safety showers are available at the worksite.
Appearance: Colorless, transparent liquid
Odor: Slight, alcohol-like
Odor Threshold: Not available
pH: Not available
Melting Point/Freezing Point: -52°C
Boiling Point: 102°C
Flash Point: 12°C (closed cup)
Evaporation Rate: Not determined
Flammability: Flammable
Vapor Pressure: 30 mmHg at 20°C
Vapor Density: 4.1
Specific Gravity: 0.95 at 20°C
Solubility: Reacts with water, forms methanol
Partition Coefficient (n-octanol/water): 1.1
Auto-ignition Temperature: 260°C
Decomposition Temperature: Not available
Viscosity: 0.7 mPa·s at 25°C
Chemical Stability: Stable under recommended storage and handling conditions.
Reactivity: Reacts with water, generating methanol and heat.
Hazardous Reactions: Contact with acids, bases, or moisture can cause rapid hydrolysis.
Conditions to Avoid: Moisture, heat, open flames, and incompatibles such as strong oxidizing agents.
Hazardous Decomposition Products: Methanol, silicon oxides, carbon monoxide, and carbon dioxide.
Acute Toxicity: Oral LD50 (rat): 7130 mg/kg. Inhalation LC50 (rat, 4h): 3.4 mg/L. Skin (rabbit): No data, but causes irritation.
Skin Corrosion/Irritation: Causes skin irritation.
Serious Eye Damage/Irritation: Causes serious eye irritation.
Respiratory Sensitization: May cause respiratory tract irritation.
Carcinogenicity: Not classified as a carcinogen by IARC, NTP, or OSHA.
Reproductive Toxicity: Not classified, but hydrolysis product methanol linked to teratogenic effects.
Specific Target Organ Toxicity: May affect central nervous system (methanol poisoning symptoms).
Other Information: Prolonged or repeated exposure can cause dermatitis and chronic respiratory effects.
Ecotoxicity: Limited data for Methyltrimethoxysilane; hydrolysis releases methanol, which is toxic to aquatic life (LC50 fish: 15,400 mg/L [96h methanol]).
Persistence and Degradability: Hydrolyzes in water to methanol and silanols; methanol degrades readily in the environment.
Bioaccumulative Potential: Low for Methyltrimethoxysilane and methanol; log Kow 1.1.
Mobility in Soil: Mobile in water, potential to leach into groundwater.
Other Adverse Effects: Formation of methanol increases risk to aquatic organisms in case of large spills.
Waste Treatment Methods: Dispose of contents and container in accordance with local, regional, and national regulations. Do not discharge to surface water or sewers.
Additional Instructions: Mix with a combustible solvent and incinerate in a chemical incinerator equipped with afterburner and scrubber.
Contaminated Packaging: Dispose of as unused product. Do not reuse empty containers.
UN Number: UN1992
UN Proper Shipping Name: Flammable Liquid, Toxic, n.o.s. (contains Methyltrimethoxysilane)
Transport Hazard Class: Class 3 (Flammable liquids), Class 6.1 (Toxic substances)
Packing Group: II
Label Requirements: Flammable liquid, toxic
Special Precautions for User: Keep away from sources of ignition, ensure containers are upright and secure.
Transport in Bulk: Follow regulations for handling bulk transfers of hazardous chemicals.
TSCA (Toxic Substances Control Act): Listed on inventory
REACH Status: Registered as a chemical substance in the EU
SARA Title III: Not subject to Section 313 reporting. Methanol (hydrolysis product) is subject to reporting.
California Proposition 65: Methanol known to the State of California to cause birth defects or other reproductive harm.
Other Regulatory Listings: Complies with workplace safety regulations in major global markets. Check local safety data requirements for your jurisdiction.
