Octamethyl cyclotetrasiloxane (CAS 556-67-2) — formula C8H24O4Si4, molecular weight 296.61; category organic chemicals.
Octamethyl cyclotetrasiloxane (CAS 556-67-2) is a chemical raw material in the organic chemicals category. Its molecular formula C8H24O4Si4 comprises 8 C, 24 H, 4 O, 4 Si atoms. Its molecular weight is about 296.61. Reported physicochemical data: melting point around 17.5 °C, boiling point around 175 °C. As a sourcing and distribution partner we help locate and compare this item across domestic and cross-border channels, arranging samples and batch orders with full COA and compliance files.
| CAS Number | 556-67-2 |
|---|---|
| Molecular Formula | C8H24O4Si4 |
| Molecular Weight | 296.61 |
| Melting Point | 17.5 °C |
| Boiling Point | 175 °C |
| Applications | Used to make methyl silicon oils, silicone fluids, and elastomers, Also used in a variety of applications including fermentation processes, instant coffee production, paper coatings and sizing |
| Category | Organic Chemicals |
Documented applications: Used to make methyl silicon oils, silicone fluids, and elastomers, Also used in a variety of applications including fermentation processes, instant coffee production, paper coatings and sizing.
Octamethyl cyclotetrasiloxane is a carbon-based organic compound with CAS registry number 556-67-2 and molecular formula C8H24O4Si4 (molecular weight 296.61), belonging to the organic chemicals segment of chemical raw materials.
CAS number: 556-67-2
Its molecular formula C8H24O4Si4 comprises 8 C, 24 H, 4 O, 4 Si atoms.
Also known as: Octamethyl cyclotetrasiloxane · 八甲基环四硅氧烷
Category: organic chemicals
The CAS registry number of Octamethyl cyclotetrasiloxane is 556-67-2.
Molecular formula C8H24O4Si4, molecular weight 296.61.
It is also registered under: Octamethyl cyclotetrasiloxane, 八甲基环四硅氧烷.
Recorded applications: Used to make methyl silicon oils, silicone fluids, and elastomers, Also used in a variety of applications including fermentation processes, instant coffee production, paper coatings and sizing.
Category: Organic Chemicals.
Packaging is agreed per order, from lab-scale packs to bulk, and confirmed with each order rather than fixed on the page. A Certificate of Analysis (COA) ships with every batch and MSDS is available; where the end use carries a regulatory limit (food contact, pharmaceutical or cosmetic), state the standard at enquiry and the grade is set against it.
Independent reference data for Octamethyl cyclotetrasiloxane (CAS 556-67-2), compiled from public chemistry databases.
| CAS Registry Number | 556-67-2 |
|---|---|
| PubChem CID | 11169 |
| Molecular formula | C8H24O4Si4 |
| IUPAC name | 2,2,4,4,6,6,8,8-octamethyl-1,3,5,7,2,4,6,8-tetraoxatetrasilocane |
| UNII (FDA) | CZ227117JE |
| Molecular Weight | 296.61 |
|---|---|
| Hydrogen Bond Donor Count | 0 |
| Hydrogen Bond Acceptor Count | 4 |
| Rotatable Bond Count | 0 |
| Exact Mass | 296.07516538 |
| Monoisotopic Mass | 296.07516538 |
| Topological Polar Surface Area | 36.9 |
| Heavy Atom Count | 16 |
| Boiling Point | 175 °C |
|---|---|
| Boiling Point | BP: 74 °C at 20 mm Hg |
| Boiling Point | 175 °C @760 [mm Hg] |
| Melting Point | 17.5 °C |
| Flash Point | 55 °C (131 °F) - closed cup |
| Flash Point | 56 °C |
| Solubility | In water, 0.056 mg/L at 23 °C |
| Density | 0.9558 @25 °C |
| Vapor Pressure | 1.05 [mmHg] |
| Vapor Pressure | 1.05 mm Hg at 25 °C |
OCTAMETHYLCYCLOTETRASILOXANE; 556-67-2; Cyclotetrasiloxane, octamethyl-; 2,2,4,4,6,6,8,8-Octamethyl-1,3,5,7,2,4,6,8-tetraoxatetrasilocane; Oktamethylcyklotetrasiloxan; OMCTS; Cyclic dimethylsiloxane tetramer; Cyclomethicone 4; NUC silicone VS 7207; Union carbide 7207; Silicone SF 1173; DTXSID7027205; KF 994; SF 1173; UC 7207; VS 7207
| Regulatory & Food Contact | FDA Cumulative Estimated Daily Intake (CEDI): FCS OCTAMETHYLCYCLOTETRASILOXANE (D4) CIR / INCI: Cosmetics ingredient -> Conditioning/Emollient; Moisturizing/Humectant CIR / INCI: Solvent; Emollient; Viscosity controlling; Antistatic; Humectant; Hair conditioning |
|---|---|
| GHS notification summary | 0.1% (2 / 4700) |
| GHS notification summary | 0.1% (2 / 4700) |
|---|---|
| Reported hazard statements | H410, H226 (72.1%), H361 (96%), H413 (89.7%) |
H361f ***: Suspected of damaging fertility [Warning Reproductive toxicity]
H410: Very toxic to aquatic life with long lasting effects [Warning Hazardous to the aquatic environment, long-term hazard]
Octamethyl cyclotetrasiloxane · CAS 556-67-2 · C8H24O4Si4. UNII CZ227117JE. Boiling Point: 175 °C; Boiling Point: BP: 74 °C at 20 mm Hg; Boiling Point: 175 °C @760 [mm Hg].
Source: PubChem / Wikidata; the batch COA governs where values differ.
Supplier: Jinan Shenghe Chemical Co., Ltd.
中文页面: 八甲基环四硅氧烷