Chemical Safety Data Sheet MSDS / SDS
Tetramethyl orthosilicate
Revision Date:2026-03-21Revision Number:1
Product identifier
- Product name: Tetramethyl orthosilicate
- CBnumber: CB6177258
- CAS: 681-84-5
- EINECS Number: 211-656-4
- Synonyms: TMOS;TETRAMETHOXYSILANE
Relevant identified uses of the substance or mixture and uses advised against
- Relevant identified uses: For R&D use only. Not for medicinal, household or other use.
- Uses advised against: none
Company Identification
- Company: Chemicalbook
- Address: Building 1, Huihuang International, Shangdi 10th Street, Haidian District, Beijing
- Telephone: 010-86108875
GHS Label elements, including precautionary statements
-
Symbol(GHS)
- Signal wordDanger
P305+P351+P338 IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing.
P303+P361+P353 IF ON SKIN (or hair): Remove/Take off Immediately all contaminated clothing. Rinse SKIN with water/shower.
P280 Wear protective gloves/protective clothing/eye protection/face protection.
P233 Keep container tightly closed.
P210 Keep away from heat/sparks/open flames/hot surfaces. — No smoking.
Hazard statements
H226 Flammable liquid and vapour
H315 Causes skin irritation
H318 Causes serious eye damage
H330 Fatal if inhaled
Substance
- Product name: Tetramethyl orthosilicate
- Synonyms: TMOS;TETRAMETHOXYSILANE
- CAS: 681-84-5
- EC number: 211-656-4
- MF: C4H12O4Si
- MW: 152.22
4.1 Description of first-aid measures
General adviceFirst aiders need to protect themselves. Show this material safety data sheet to the doctor in attendance.
If inhaled
After inhalation: fresh air. Immediately call in physician. If breathing stops: immediately apply artificial respiration, if necessary also oxygen.
In case of skin contact
In case of skin contact: Take off immediately all contaminated clothing. Rinse skin with water/ shower.
In case of eye contact
After eye contact: rinse out with plenty of water. Immediately call in ophthalmologist.
Remove contact lenses.
If swallowed
Remove contact lenses.
After swallowing: immediately make victim drink water (two glasses at most). Consult a physician.
4.2 Most important symptoms and effects, both acute and delayed
The most important known symptoms and effects are described in the labelling (see section 2) and/or in section 11
4.3 Indication of any immediate medical attention and special treatment needed
No data available
4.4 Notes to physician
No data available
5.1 Extinguishing media
Suitable extinguishing mediaWater Foam Carbon dioxide (CO2) Dry powder
Unsuitable extinguishing media
For this substance/mixture no limitations of extinguishing agents are given.
5.2 Special hazards arising from the substance or mixture
Carbon oxides silicon oxides
Combustible.
Vapors are heavier than air and may spread along floors.
Forms explosive mixtures with air at elevated temperatures.
Development of hazardous combustion gases or vapours possible in the event of fire.
Combustible.
Vapors are heavier than air and may spread along floors.
Forms explosive mixtures with air at elevated temperatures.
Development of hazardous combustion gases or vapours possible in the event of fire.
5.3 Advice for firefighters
Stay in danger area only with self-contained breathing apparatus. Prevent skin contact by keeping a safe distance or by wearing suitable protective clothing.
Remove container from danger zone and cool with water. Suppress (knock down) gases/vapors/mists with a water spray jet. Prevent fire extinguishing water from contaminating surface water or the ground water system.
Remove container from danger zone and cool with water. Suppress (knock down) gases/vapors/mists with a water spray jet. Prevent fire extinguishing water from contaminating surface water or the ground water system.
NFPA 704
3
3
1
| HEALTH | 3 | Short exposure could cause serious temporary or moderate residual injury (e.g. liquid hydrogen, sulfuric acid, calcium hypochlorite, hexafluorosilicic acid) | |
| FIRE | 3 | Liquids and solids (including finely divided suspended solids) that can be ignited under almost all ambient temperature conditions . Liquids having a flash point below 22.8 °C (73 °F) and having a boiling point at or above 37.8 °C (100 °F) or having a flash point between 22.8 and 37.8 °C (73 and 100 °F). (e.g. gasoline, acetone) | |
| REACT | 1 | Normally stable, but can become unstable at elevated temperatures and pressures (e.g. propene) | |
| SPEC. HAZ. |
6.1 Personal precautions, protective equipment and emergency procedures
Advice for non-emergency personnel: Do not breathe vapors, aerosols. Avoid substance contact. Ensure adequate ventilation. Keep away from heat and sources of ignition.
Evacuate the danger area, observe emergency procedures, consult an expert.
For personal protection see section 8.
Evacuate the danger area, observe emergency procedures, consult an expert.
For personal protection see section 8.
6.2 Environmental precautions
Do not let product enter drains. Risk of explosion.
6.3 Methods and materials for containment and cleaning up
Cover drains. Collect, bind, and pump off spills. Observe possible material restrictions (see sections 7 and 10). Take up carefully with liquid-absorbent material (e.g.
Chemizorb®). Dispose of properly. Clean up affected area.
Chemizorb®). Dispose of properly. Clean up affected area.
6.4 Reference to other sections
For disposal see section 13.
7.1 Precautions for safe handling
Advice on safe handlingWork under hood. Do not inhale substance/mixture. Avoid generation of vapours/aerosols.
Advice on protection against fire and explosion
Keep away from open flames, hot surfaces and sources of ignition.Take precautionary measures against static discharge.
Hygiene measures
Immediately change contaminated clothing. Apply preventive skin protection. Wash hands and face after working with substance.
For precautions see section 2.2.
For precautions see section 2.2.
7.2 Conditions for safe storage, including any incompatibilities
Storage conditionsKeep container tightly closed in a dry and well-ventilated place. Keep away from heat and sources of ignition. Keep locked up or in an area accessible only to qualified or authorized persons.
Recommended storage temperature see product label.
Storage class
Recommended storage temperature see product label.
Storage class (TRGS 510): 3: Flammable liquids
8.1 Control parameters
Ingredients with workplace control parameters| ['Component', 'CAS-No.', 'Value', 'Control\nparameters', 'Basis'] | ['Silicic acid\ntetramethyl ester', '681-84-5', 'TWA', '1 ppm', 'USA. ACGIH Threshold Limit\nValues (TLV)'] | ['', '', 'TWA', '1 ppm6\nmg/m3', 'USA. NIOSH Recommended\nExposure Limits'] |
|---|
PEL 1 ppm6 California permissible exposure mg/m3 limits for chemical contaminants (Title 8, Article 107)
8.2 Exposure controls
Appropriate engineering controlsImmediately change contaminated clothing. Apply preventive skin protection. Wash hands and face after working with substance.
Personal protective equipment
Eye/face protection
Use equipment for eye protection tested and approved under appropriate government standards such as NIOSH (US) or EN 166(EU). Tightly fitting safety goggles
Skin protection
This recommendation applies only to the product stated in the safety data sheet, supplied by us and for the designated use. When dissolving in or mixing with other substances and under conditions deviating from those stated in EN 16523-1 please contact the supplier of CE-approved gloves (e.g. KCL GmbH, D-36124 Eichenzell,
Internet: www.kcl.de).
Full contact
Material: Nitrile rubber
Minimum layer thickness: 0.4 mm
Break through time: 480 min
Material tested:Camatril® (KCL 730 / Aldrich Z677442, Size M)
This recommendation applies only to the product stated in the safety data sheet, supplied by us and for the designated use. When dissolving in or mixing with other substances and under conditions deviating from those stated in EN 16523-1 please contact the supplier of CE-approved gloves (e.g. KCL GmbH, D-36124 Eichenzell,
Internet: www.kcl.de).
Splash contact
Material: Chloroprene
Minimum layer thickness: 0.65 mm
Break through time: 240 min
Material tested:KCL 720 Camapren®
Internet: www.kcl.de).
Full contact
Material: Nitrile rubber
Minimum layer thickness: 0.4 mm
Break through time: 480 min
Material tested:Camatril® (KCL 730 / Aldrich Z677442, Size M)
This recommendation applies only to the product stated in the safety data sheet, supplied by us and for the designated use. When dissolving in or mixing with other substances and under conditions deviating from those stated in EN 16523-1 please contact the supplier of CE-approved gloves (e.g. KCL GmbH, D-36124 Eichenzell,
Internet: www.kcl.de).
Splash contact
Material: Chloroprene
Minimum layer thickness: 0.65 mm
Break through time: 240 min
Material tested:KCL 720 Camapren®
Body Protection
Flame retardant antistatic protective clothing.
Respiratory protection
required when vapours/aerosols are generated. Our recommendations on filtering respiratory protection are based on the following standards: DIN EN 143, DIN 14387 and other accompanying standards relating to the used respiratory protection system.
Control of environmental exposure
Do not let product enter drains. Risk of explosion.
Information on basic physicochemical properties
- a) Physical stateliquid
- b) Colorcolorless, to, yellow
- c) Odoraromatic
- d) Melting point/freezing pointMelting point/ range: 3 °C at 1,013 hPa - OECD Test Guideline 102
- e) Initial boiling point and boiling range121 - 122 °C at 1,013 hPa
- f) Flammability (solid, gas)No data available
- g) Upper/lower flammability or explosive limitsUpper explosion limit: 23.8 %(V)
Lower explosion limit: 0.88 %(V) - DIN 51649 - h) Flash point26 °C - closed cup
- i) Autoignition temperature245 °C at 1,013 hPa - DIN 51794
- j) Decomposition temperatureNo data available
- k) pHNo data available
- l) ViscosityViscosity, kinematic: No data available
Viscosity, dynamic: 0.7 mPa.s at 20 °C - m) Water solubilityhydrolyzes
- n) Partition coefficient n-octanol/waterNo data available
- o) Vapor pressure13 hPa at 20 °C - OECD Test Guideline 104 18 hPa at 25 °C - OECD Test Guideline 104
- p) Density1.03 g/cm3 at 20 °C
- Relative density1.023 g/mL at 25 °C(lit.)
- q) Relative vapor density5.25 (vs air)
- r) Particle characteristicsNo data available
- s) Explosive propertiesNo data available
- t) Oxidizing propertiesnone
9.2 Other safety information
Relative vapor density5.26 - (Air = 1.0)
10.1 Chemical stability
The product is chemically stable under standard ambient conditions (room temperature) .
10.2 Possibility of hazardous reactions
Exothermic reaction with:
Alkali metals
Alkaline earth metals
Oxidizing agents acids
Water
Possible decomposition products in case of hydrolyzis are:
Methanol
Alkali metals
Alkaline earth metals
Oxidizing agents acids
Water
Possible decomposition products in case of hydrolyzis are:
Methanol
10.3 Conditions to avoid
Heating.
10.4 Incompatible materials
No data available
10.5 Hazardous decomposition products
In the event of fire: see section 5
11.1 Information on toxicological effects
Acute toxicityLD50 Oral - Rat - male and female - > 2,500 mg/kg (OECD Test Guideline 423)
Remarks: The value is given in analogy to the following substances: tetraethyl silicate
LC50 Inhalation - Rat - male - 4 h - 0.39 mg/l - vapor (OECD Test Guideline 403)
Symptoms: Possible damages:, mucosal irritations, Lung edema
LD50 Dermal - Rabbit - 17,544 mg/kg
Remarks: (RTECS)
Skin corrosion/irritation
Remarks: The value is given in analogy to the following substances: tetraethyl silicate
LC50 Inhalation - Rat - male - 4 h - 0.39 mg/l - vapor (OECD Test Guideline 403)
Symptoms: Possible damages:, mucosal irritations, Lung edema
LD50 Dermal - Rabbit - 17,544 mg/kg
Remarks: (RTECS)
Skin - Rat
Result: Irritating to skin. - 4 h (OECD Test Guideline 404)
Serious eye damage/eye irritation
Result: Irritating to skin. - 4 h (OECD Test Guideline 404)
Remarks: Risk of blindness! (ECHA)
Respiratory or skin sensitization
Buehler Test - Guinea pig
Result: negative (OECD Test Guideline 406)
Remarks: The value is given in analogy to the following substances: tetraethyl silicate
Germ cell mutagenicity
Result: negative (OECD Test Guideline 406)
Remarks: The value is given in analogy to the following substances: tetraethyl silicate
Test Type: Ames test
Test system: Escherichia coli/Salmonella typhimurium
Metabolic activation: with and without metabolic activation
Method: OECD Test Guideline 471
Result: negative
Test Type: In vivo micronucleus test
Species: Rat
Cell type: Bone marrow
Application Route: inhalation (vapor)
Method: OECD Test Guideline 474
Result: negative
Carcinogenicity
Test system: Escherichia coli/Salmonella typhimurium
Metabolic activation: with and without metabolic activation
Method: OECD Test Guideline 471
Result: negative
Test Type: In vivo micronucleus test
Species: Rat
Cell type: Bone marrow
Application Route: inhalation (vapor)
Method: OECD Test Guideline 474
Result: negative
Classified based on available data. For more details, see section 2
Reproductive toxicity
Classified based on available data. For more details, see section 2
Specific target organ toxicity - single exposure
Classified based on available data. For more details, see section 2
Specific target organ toxicity - repeated exposure
Classified based on available data. For more details, see section 2
Aspiration hazard
Classified based on available data. For more details, see section 2
11.2 Additional Information
Blindness, Effects due to ingestion may include:, Nausea, Vomiting, Gastrointestinal disturbance, Dizziness, Difficulty in breathing, Weakness, Drowsiness, Unconsciousness
To the best of our knowledge, the chemical, physical, and toxicological properties have not been thoroughly investigated.
Systemic effects:
After absorption of large quantities:
Damage to:
Liver
Kidney
Other dangerous properties can not be excluded.
This substance should be handled with particular care.
To the best of our knowledge, the chemical, physical, and toxicological properties have not been thoroughly investigated.
Systemic effects:
After absorption of large quantities:
Damage to:
Liver
Kidney
Other dangerous properties can not be excluded.
This substance should be handled with particular care.
12.1 Toxicity
Toxicity to fish semi-static test LC50 - Danio rerio (zebra fish) - > 1,000 mg/l - 96 h (OECD Test Guideline 203)
Remarks: The value is given in analogy to the following substances: tetraethyl silicate
Toxicity to daphnia flow-through test EC50 - Daphnia magna (Water flea) - > 500 mg/l - and other aquatic 48 h invertebrates (OECD Test Guideline 202)
Remarks: The value is given in analogy to the following substances: tetraethyl silicate
Toxicity to algae static test ErC50 - Pseudokirchneriella subcapitata (green algae) - > 100 mg/l - 72 h (OECD Test Guideline 201)
Remarks: The value is given in analogy to the following substances: tetraethyl silicate
Toxicity to bacteria static test EC50 - activated sludge - > 100 mg/l - 3 h (OECD Test Guideline 209)
Remarks: The value is given in analogy to the following substances: tetraethyl silicate
Remarks: The value is given in analogy to the following substances: tetraethyl silicate
Toxicity to daphnia flow-through test EC50 - Daphnia magna (Water flea) - > 500 mg/l - and other aquatic 48 h invertebrates (OECD Test Guideline 202)
Remarks: The value is given in analogy to the following substances: tetraethyl silicate
Toxicity to algae static test ErC50 - Pseudokirchneriella subcapitata (green algae) - > 100 mg/l - 72 h (OECD Test Guideline 201)
Remarks: The value is given in analogy to the following substances: tetraethyl silicate
Toxicity to bacteria static test EC50 - activated sludge - > 100 mg/l - 3 h (OECD Test Guideline 209)
Remarks: The value is given in analogy to the following substances: tetraethyl silicate
12.2 Persistence and degradability
Biodegradability aerobic - Exposure time 28 d
Result: 98 % - Readily biodegradable.
(Regulation (EC) No. 440/2008, Annex, C.4-A)
Remarks: The value is given in analogy to the following substances: tetraethyl silicate
Result: 98 % - Readily biodegradable.
(Regulation (EC) No. 440/2008, Annex, C.4-A)
Remarks: The value is given in analogy to the following substances: tetraethyl silicate
12.3 Bioaccumulative potential
No data available
12.4 Mobility in soil
No data available
12.5 Results of PBT and vPvB assessment
PBT/vPvB assessment not available as chemical safety assessment not required/not conducted
12.6 Endocrine disrupting properties
No data available
12.7 Other adverse effects
Possible decomposition products in case of hydrolyzis are:
Methanol
Discharge into the environment must be avoided.
Methanol
Discharge into the environment must be avoided.
13.1 Waste treatment methods
Product
Offer surplus and non-recyclable solutions to a licensed disposal company.
Offer surplus and non-recyclable solutions to a licensed disposal company.
14.1 UN number
ADR/RID: 2606
IMDG: 2606
IATA-DGR: 2606
IMDG: 2606
IATA-DGR: 2606
14.2 UN proper shipping name
ADR/RID: METHYL ORTHOSILICATE
IMDG: METHYL ORTHOSILICATE
IATA-DGR: Methyl orthosilicate
Passenger Aircraft: Not permitted for transport
Cargo Aircraft: Not permitted for transport
IMDG: METHYL ORTHOSILICATE
IATA-DGR: Methyl orthosilicate
Passenger Aircraft: Not permitted for transport
Cargo Aircraft: Not permitted for transport
14.3 Transport hazard class(es)
ADR/RID: 6.1 (3)
IMDG: 6.1 (3)
IATA-DGR: 6.1 (3)
IMDG: 6.1 (3)
IATA-DGR: 6.1 (3)
14.4 Packaging group
ADR/RID: I
IMDG: I
IATA-DGR: -
IMDG: I
IATA-DGR: -
14.5 Environmental hazards
ADR/RID: no
IMDG Marine pollutant: no
IATA-DGR: no
IMDG Marine pollutant: no
IATA-DGR: no
14.6 Special precautions for user
Based on chemical properties, choose appropriate tools and conditions of transport.
Transporting tools shall be equipped with appropriate and sufficient firefighting equipment and emergency leaking installations. If transporting by road, please go along the specified route.
Transporting tools shall be equipped with appropriate and sufficient firefighting equipment and emergency leaking installations. If transporting by road, please go along the specified route.
14.7 Incompatible materials
15.1 Safety, health and environmental regulations/legislation specific for the substance or mixture
National regulatory information
Law on the Prevention and Control of Occupational Diseases
Regulations on Safety Management of Hazardous Chemicals
Catalogue of Hazardous Chemicals : Listed
Other regulations
Please pay attention on the waste treatment should also comply with local regulations requirement.
Law on the Prevention and Control of Occupational Diseases
Regulations on Safety Management of Hazardous Chemicals
Catalogue of Hazardous Chemicals : Listed
Other regulations
Please pay attention on the waste treatment should also comply with local regulations requirement.
Abbreviations and acronyms
CAS: Chemical Abstracts Service
TWA: Time-Weighted Average
STEL: Short-Term Exposure Limit
LD50: Lethal Dose 50%
LC50: Lethal Concentration 50%
EC50: Effective Concentration 50%
PEL: Permissible Exposure Limit
TLV: Threshold Limit Value
IMDG: International Maritime Dangerous Goods Code
IATA: International Air Transport Association
ADR: European Agreement concerning the International Carriage of Dangerous Goods by Road
DOT: US Department of Transportation
NFPA: National Fire Protection Association
NIOSH: National Institute for Occupational Safety and Health
OSHA: Occupational Safety and Health Administration
TWA: Time-Weighted Average
STEL: Short-Term Exposure Limit
LD50: Lethal Dose 50%
LC50: Lethal Concentration 50%
EC50: Effective Concentration 50%
PEL: Permissible Exposure Limit
TLV: Threshold Limit Value
IMDG: International Maritime Dangerous Goods Code
IATA: International Air Transport Association
ADR: European Agreement concerning the International Carriage of Dangerous Goods by Road
DOT: US Department of Transportation
NFPA: National Fire Protection Association
NIOSH: National Institute for Occupational Safety and Health
OSHA: Occupational Safety and Health Administration
Disclaimer:
The information in this MSDS is only applicable to the specified product, unless otherwise specified, it is not applicable to the mixture of this product and other substances. This MSDS only provides information on the safety of the product for those who have received the appropriate professional training for the user of the product. Users of this MSDS must make independent judgments on the applicability of this SDS. The authors of this MSDS will not be held responsible for any harm caused by the use of this MSDS.