Octamethyltrisiloxane
Octamethyltrisiloxane is an organosiloxane that is trisiloxane in which all the hydrogens have been replaced by methyl groups. — ChEBI
- IUPAC name
- dimethyl-bis(trimethylsilyloxy)silane
- Molecular formula
- C8H24O2Si3
- Molecular weight
- 236.53 g/mol
- Exact mass
- 236.10840961 Da
- Topological polar surface area
- 18.5 Ų
- Hydrogen-bond donors
- 0
- Hydrogen-bond acceptors
- 2
- Covalent units
- 1
- Defined stereocentres
- 0
Also known as
16 more reported names
External database identifiers
- ChEBI:CHEBI:31498
- ChEBI:CHEBI:9147
- ChEMBL:CHEMBL2142985
- EPA DTXSID:DTXSID9040710
- PubMed:22575024
- PubMed:17389072
- PubMed:15464816
- PubMed:12661663
Evidence from additional scientific databases
EMBL-EBI ChEBI
octamethyltrisiloxane
An organosiloxane that is trisiloxane in which all the hydrogens have been replaced by methyl groups.
- Formula
- C8H24O2Si3
- Average mass
- 236.536 g/mol
- Monoisotopic mass
- 236.10841 Da
- Formal charge
- 0
- organosiloxane — is a (CHEBI:48150)
- organosiloxane — is a (CHEBI:48150)
Additional curated names
Cross-references from this source
Mapped by: Exact CAS cross-reference in the ChEBI compound record. Source updated: 2019-11-04. Retrieved: 2026-08-31. Open source record
NIH PubChem PUG-View
Attributed physical-property, hazard, environmental and use annotations.
- Physical Description: Liquid Source: EPA Chemical Data Reporting (CDR)
- Physical Description: Liquid; [Merck Index] Colorless odorless liquid; [Acros Organics MSDS] Source: Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
- Vapor Pressure: 3.34 [mmHg] Source: Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
- Note: This chemical does not meet GHS hazard criteria for 11.1% (49 of 443) of reports. Source: European Chemicals Agency (ECHA)
- Signal: Warning Source: European Chemicals Agency (ECHA)
- GHS Hazard Statements: H226 (88.9%): Flammable liquid and vapor [Warning Flammable liquids]; H413 (27.1%): May cause long lasting harmful effects to aquatic life [Hazardous to the aquatic environment, long-term hazard] Source: European Chemicals Agency (ECHA)
- Precautionary Statement Codes: P210, P233, P240, P241, P242, P243, P273, P280, P303+P361+P353, P370+P378, P403+P235, and P501 (click each P-code to see the statement) Source: European Chemicals Agency (ECHA)
- ECHA C&L Notifications Summary: Aggregated GHS information provided per 443 reports by companies from 6 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.; Reported as not meeting GHS hazard criteria per 49 of 443 reports by companies.; There are 5 notifications provided by 394 of 443 reports by companies with hazard statement code(s).; Information may vary between notifications depending on impurities, additives, and other factors. The percentage value in parenthesis indicates the notified classification ratio from companies that provide hazard codes. Only hazard codes with percentage values above 10% are shown. For more detailed information, please visit ECHA C&L website. Source: European Chemicals Agency (ECHA)
- Consumer Uses: Diluent Source: EPA Chemical Data Reporting (CDR)
- Industry Uses: Intermediate; Diluent; Heat transferring agent; Other Source: EPA Chemical Data Reporting (CDR)
- Sources/Uses: Used as a base for extreme temperature silicone oils/fluids and as a foam suppressant in petroleum lubricating oils; [Merck Index] Used mainly to make polydimethylsiloxane (PDMS) polymers, oligomers, and mixtures; Also used to make basic chemicals, paints, coatings, adhesives, soaps, cleaning compounds, toiletries, plastics, semiconductors, and other electronic components, and in building construction, lubricants, diluents, solvents, and cosmetics; [Government of Canada - Chemicals Management Plan] Source: Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
- Industrial Processes with risk of exposure: Semiconductor Manufacturing [Category: Industry] Source: Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
Mapped by: Existing checksum-valid CAS to unique PubChem CID match. Retrieved: 2026-08-31. Open source record
Scientific classifications and hazard annotations provide context and do not replace the market-specific regulatory decision shown above.
Additional source coverage and match status
| Source | Result | Checked |
|---|---|---|
| EMBL-EBI ChEBI | Exact match | 2026-08-31 |
| NIH PubChem PUG-View | Exact match | 2026-08-31 |
A recorded no-match is useful evidence that the source was checked; it is not a claim that the substance does not exist elsewhere.
Retrieved from NIH PubChem on 2026-08-31 by checksum-valid CAS matching. Chemical properties do not replace the regulatory decision on this page.