Product Name: Tetrabutylorthosilane
Synonyms: Tetrabutyl silicate, Orthosilicic acid tetrabutyl ester
Chemical Formula: Si(OC4H9)4
CAS Number: 78-08-0
Molecular Weight: 320.6 g/mol
Recommended Use: Industrial chemical, used in sol-gel processes, surface treatment, and chemical synthesis
Supplier Contact: Provided on purchase invoice or request
Emergency Contact: National Poison Control Center or local emergency numbers
Hazard Classification: Flammable liquid, eye irritant, skin irritant, possible respiratory irritant
GHS Label Elements: Signal word: Danger; Pictograms: Flame, exclamation mark
Hazard Statements: Flammable liquid and vapor; causes skin and eye irritation; harmful if inhaled
Precautionary Statements: Keep away from heat, sparks, open flames, and hot surfaces; avoid contact with skin and eyes; use only outdoors or in well-ventilated area
Health Hazards: Prolonged or repeated contact can defat the skin, leading to irritation and dermatitis; inhalation of vapor can cause central nervous system effects such as headache or dizziness
Environmental Hazards: Harmful to aquatic life with long lasting effects; avoid release to the environment
Chemical Name: Tetrabutylorthosilane
Concentration: 98–100%
Impurities: Trace amounts of butanol or other butyl silicate compounds can be present
CAS Number: 78-08-0
Inhalation: Remove affected person to fresh air immediately; seek medical attention if symptoms like dizziness or breathing difficulty develop
Skin Contact: Immediately wash skin with plenty of soap and water; remove contaminated clothing; seek medical advice if irritation occurs
Eye Contact: Rinse carefully with water for several minutes; remove contact lenses if easy to do; continue rinsing and get medical help
Ingestion: Rinse mouth; do not induce vomiting; seek medical assistance
Most Important Symptoms: Skin redness, eye irritation, drowsiness, or dizziness
Suitable Extinguishing Media: Alcohol-resistant foam, dry chemical powder, carbon dioxide, water spray (fog)
Unsuitable Extinguishing Media: Direct water jets
Specific Hazards: Vapors can form explosive mixtures with air; combustion produces toxic fumes including silicon oxides and carbon oxides
Special Protective Equipment: Firefighters should wear full protective gear and self-contained breathing apparatus
Firefighting Instructions: Keep containers cool with water spray; approach from upwind to avoid vapors
Personal Precautions: Evacuate area; ventilate confined spaces; wear protective equipment including gloves and eye protection
Environmental Precautions: Prevent entry into drains, watercourses, and soil
Methods for Cleaning Up: Contain spillage with non-combustible absorbent material (e.g., sand, earth); collect in suitable, labeled containers for proper disposal; clean spill area thoroughly with water after material removal; ventilate area to dissipate vapors
Handling: Use under adequate ventilation or in a chemical fume hood; avoid contact with skin, eyes, and clothing; prevent inhalation of vapor; keep ignition sources away
Storage: Store in tightly closed original containers in a cool, dry, well-ventilated place away from sources of heat, flames, and incompatible substances like strong acids and oxidizers; segregation from foods and feedstuffs recommended; keep container upright and well-sealed
Engineering Controls: Use mechanical exhaust or chemical fume hoods to maintain airborne concentrations below permissible limits
Respiratory Protection: NIOSH-approved respirator if vapor/mist exposure limit exceeded
Skin Protection: Wear chemical-resistant gloves such as nitrile or neoprene; long-sleeved clothing is recommended
Eye Protection: Safety goggles or face shield required when handling bulk quantities
Occupational Exposure Limit: No specific OEL for tetrabutylorthosilane; minimize exposure as a good industrial practice
Other Protective Equipment: Emergency eyewash stations and safety showers should be easily accessible
Appearance: Clear, colorless to pale yellow liquid
Odor: Mild, alcoholic odor
Boiling Point: About 290°C
Melting Point: -78°C
Flash Point: Approximately 77°C (closed cup)
Auto-ignition Temperature: Not readily available
Vapor Pressure: Low at room temperature
Density: About 0.94 g/cm³ at 20°C
Solubility: Practically insoluble in water; miscible with many organic solvents
Viscosity: 6.5 mPa·s at 25°C
Partition Coefficient (n-octanol/water): Not determined
Evaporation Rate: Not established
Chemical Stability: Stable under recommended storage and handling conditions
Reactivity: May react with water, acids, or alcohols releasing butanol and forming gels
Possibility of Hazardous Reactions: Exothermic hydrolysis, polymerization in the presence of moisture
Incompatible Materials: Strong acids, oxidizers, alkalis, amines
Decomposition Products: Butanol, silicon oxides, carbon oxides upon combustion or hydrolysis
Routes of Exposure: Inhalation, skin contact, eye contact, ingestion
Acute Toxicity: Oral LD50 (rat): 2,340 mg/kg; inhalation data: Not established for vapor
Irritation: Causes moderate skin and eye irritation
Corrosivity: Not corrosive but may cause drying and cracking of the skin
Chronic Effects: Prolonged exposure can cause symptoms related to nervous system depression, dermatitis
Carcinogenicity: Not listed by IARC, NTP, OSHA
Reproductive Toxicity: Animal studies insufficient for assessment
Specific Target Organ Toxicity: Can affect the central nervous system at high concentrations due to butanol formation
Ecotoxicity: Moderately toxic to aquatic organisms; hydrolysis byproducts (butanol) present acute danger to aquatic environments
Persistence and Degradability: Hydrolyzes in water forming butanol and silicic acid; organics may persist in some environments
Bioaccumulation: Low potential for bioaccumulation
Mobility in Soil: Liquid; can seep into ground and water systems if not contained, but rapidly hydrolyzes to less harmful products
Other Adverse Effects: Avoid uncontrolled release, especially near bodies of water
Waste Treatment Methods: Dispose of as hazardous waste in accordance with local, state, and federal regulations
Product Disposal: Incineration in a licensed facility recommended; do not pour down the drain
Contaminated Packaging: Triple-rinse empty containers; offer for recycling if available
Precautions: Do not allow product or rinse water to reach sewers or water bodies; consult with licensed waste management provider
UN Number: UN 1993
UN Proper Shipping Name: Flammable Liquids, N.O.S. (Tetrabutylorthosilane)
Transport Hazard Class: 3 (Flammable liquid)
Packing Group: III
Labels Required: Flammable liquid
Special Precautions: Store and transport upright; protect from physical damage, heat, sparks, or open flames
Transport Regulations: Subject to ADR, IMDG, and IATA rules for flammable liquids
OSHA Status: Classified as hazardous chemical
TSCA Inventory: Listed
SARA Title III: Not specifically listed under Section 302, 304, or 313, but butanol byproduct may trigger reporting
REACH Registration: Required for import into EU above threshold quantities
WHMIS Classification (Canada): Class B2 (flammable liquid), Class D2B (toxic material causing other effects)
California Proposition 65: Not listed
Other Regulatory Information: Dispose and handle according to regional safety, health, and environmental regulations; subject to workplace safety and handling guidelines in all jurisdictions where manufactured, transported, or used
