Tetraethyl orthosilicate
ALDRICH/86578 - ≥99.0% (GC)
Synonym: Orthosilicic acid tetraethyl ester; Silicon tetraethoxide; TEOS; Tetraethoxysilane; Tetraethoxysilicon(IV); Tetraethyl silicate; Orthosilicic acid tetraethyl ester; TEOS; Tetraethoxysilane
CAS Number: 78-10-4
Empirical Formula (Hill Notation): C8H20O4Si
Molecular Weight: 208.33
EC Number: 201-083-8
MDL Number: MFCD00009062
Linear Formula: Si(OC2H5)4
Product Type: Chemical
| assay | ≥99.0% (GC) |
| bp | 168 °C (lit.) |
| density | 0.933 g/mL at 20 °C (lit.) |
| form | liquid |
| InChI | 1S/C8H20O4Si/c1-5-9-13(10 |
| InChI key | BOTDANWDWHJENH-UHFFFAOYSA |
| Quality Level | 200 ![]() |
| refractive index | n |
| n |
|
| SMILES string | CCO[Si](OCC)(OCC)OCC |
| technique(s) | GC/GC: suitable |
| vapor density | 7.2 (vs air) |
| vapor pressure | <1 mmHg ( 20 °C) |
| Application: | Commonly used as a precursor to prepare xerogel |
| Application: | Tetraethyl orthosilicate (TEOS) can be used: • As a reagent along with ferric chloride in the synthesis of dihydropyrimidinones. • As a modifier in fabrication of humidity sensing material, poly(2-acrylamido-2-methy • As a medium to synthesize triarylamines and diaryl ethers via copper catalyzed, ligand free-Ullmann reaction. • As a precursor for the preparation of silica xerogel which finds application in pharmaceutical drug carriers. • As a precursor for the synthesis of spherical silica particles by Stober process. |
| Application: | Will interact with dodecylamine in the formation of intercalation compounds of H+-magadiite and used in a study of mixed-metal bioactive glasses. |
| General description: | Tetraethyl orthosilicate (TEOS) is an inorganic material that can be used as a silica source for the synthesis of silica-based materials such as silicon dioxide, silicon oxycarbides, silanol, siloxane polymer, and organosilicon thin films for a variety of applications. It can also be used in the synthesis of blended membranes, and the production of aerogel. Other applications include coatings for carpets and other objects. |
| Packaging: | 1 L in glass bottle |
| Packaging: | 250 mL in glass bottle |
| Symbol | ![]() GHS02,GHS07 |
| Signal word | Warning |
| Hazard statements | H226 - H319 - H332 - H335 |
| Precautionary statements | P210 - P233 - P240 - P241 - P304 + P340 + P312 - P305 + P351 + P338 |
| Hazard Codes | Xn |
| Risk Statements | 10-20-36/37 |
| RIDADR | UN1292 - class 3 - PG 3 - Tetraethyl silicate |
| WGK Germany | WGK 1 |
| Flash Point(F) | 113.0 °F - closed cup |
| Flash Point(C) | 45 °C - closed cup |
| Purity | ≥99.0% (GC) |
| bp | 168 °C (lit.) |
| Density | 0.933 g/mL at 20 °C (lit.) |
| Refractive Index | n |
| UNSPSC | 12352103 |



