Cyclohexasiloxane

Description

Cyclohexasiloxane · CAS 540-97-6 · C12H36O6Si6. UNII XHK3U310BA. Boiling Point: 245 °C; Melting Point: -3 °C; Flash Point: 91 °C (196 °F) - closed cup.

Identification

CAS Registry Number	540-97-6
PubChem CID	10911
Molecular formula	C12H36O6Si6
IUPAC name	2,2,4,4,6,6,8,8,10,10,12,12-dodecamethyl-1,3,5,7,9,11-hexaoxa-2,4,6,8,10,12-hexasilacyclododecane
UNII (FDA)	XHK3U310BA

Computed Descriptors

Molecular Weight	444.92
Hydrogen Bond Donor Count	0
Hydrogen Bond Acceptor Count	6
Rotatable Bond Count	0
Exact Mass	444.11274807
Monoisotopic Mass	444.11274807
Topological Polar Surface Area	55.4
Heavy Atom Count	24
Formal Charge	0
Complexity	320

Physical & Chemical Properties

Boiling Point	245 °C
Melting Point	-3 °C
Flash Point	91 °C (196 °F) - closed cup
Solubility	In water, 0.0051 mg/L at 23 °C
Density	0.9672 g/cu cm at 25 °C
Vapor Pressure	0.0169 mm Hg at 25 °C
LogP	log Kow = 8.87
Viscosity	6.62 cSt
Surface Tension	19.2 mN/m at 20 °C; 18.8 mN/m at 25 °C

Physical description & handling notes

• CBI; Liquid; Other Solid; Liquid
• Oily liquid
• Clear, siloxane fluid
• Odorless
• Henry's Law constant = 25.0 atm-cu m/mole at 25 °C
• Stable under recommended storage conditions.

Regulatory Status

Regulatory & Food Contact	FDA Cumulative Estimated Daily Intake (CEDI): FCS DODECAMETHYLCYCLOHEXASILOXANE (D6) CIR / INCI: Cosmetics ingredient -> Conditioning/Emollient; Moisturizing/Humectant; Other (Specify); Solvent CIR / INCI: Hair conditioning; Solvent; Emollient
GHS notification summary	81.5% (365 / 448)

GHS Hazard Classification

GHS notification summary	81.5% (365 / 448)
Reported hazard statements	H413 (12.9%), H227

Documented Uses

• Electronics, furniture, health-care products, cookware, and medical devices
• Field of application: Surface treatments, paint, lacquers, and varnishes. /From table/
• Cyclomethicone formulation containing dodecamethylcyclohexasiloxane (D6), decamethylcyclopentasiloxane (D5), and octamethylcyclotetrasiloxane (D4) are used in consumer products such as body lotion, hair styling products, lipstick, and deodorants.
• Limited number of applications including some cosmetics, where it provides certain application-related benefits preferred by customers
• Cosmetics -> Hair conditioning; Solvent; Emollient
• Cosmetics product ingredient: Dodecamethylcyclohexasiloxane (D6) (Cyclohexasiloxane)

Synonyms

DODECAMETHYLCYCLOHEXASILOXANE; 540-97-6; Cyclohexasiloxane, dodecamethyl-; Cyclomethicone 6; XHK3U310BA; XIAMETER PMX-0246; DTXSID6027183; RefChem:590100; DTXCID507183; 208-762-8; 2,2,4,4,6,6,8,8,10,10,12,12-dodecamethyl-1,3,5,7,9,11-hexaoxa-2,4,6,8,10,12-hexasilacyclododecane; Cyclohexasiloxane; MFCD00144215; Simethicone Impurity 5; 2,2,4,4,6,6,8,8,10,10,12,12-Dodecamethylcyclohexasiloxane; S08515

Frequently Asked Questions

What are the CAS number and molecular formula of Cyclohexasiloxane?

CAS 540-97-6; molecular formula C12H36O6Si6; molecular weight — g/mol.

What other names is Cyclohexasiloxane known by?

DODECAMETHYLCYCLOHEXASILOXANE, 540-97-6, Cyclohexasiloxane, dodecamethyl-, Cyclomethicone 6, XHK3U310BA, XIAMETER PMX-0246.

What is the regulatory status of Cyclohexasiloxane?

Documented regulatory listings: FDA Cumulative Estimated Daily Intake (CEDI): FCS; DODECAMETHYLCYCLOHEXASILOXANE (D6); CIR / INCI: Cosmetics ingredient -> Conditioning/Emollient; Moisturizing/Humectant; Other (Specify); Solvent.

Is Cyclohexasiloxane classified as hazardous?

81.5% of GHS notifications report no hazard classification (365 of 448).

What are the key physical properties of Cyclohexasiloxane?

Boiling Point: 245 °C; Melting Point: -3 °C; Flash Point: 91 °C (196 °F) - closed cup; Solubility: In water, 0.0051 mg/L at 23 °C.

Facts on this page are taken from PubChem (US National Library of Medicine) and Wikidata. Grade-specific data — assay, moisture, particle size, packaging, shelf life — is issued per batch on the COA and is not published here.