OCTAMETHYLCYCLOTETRASILOXANE

OCTAMETHYLCYCLOTETRASILOXANE = OCTAMETHYLTETRASILOXANE = D4 

CAS Number: 556-67-2 
EC Number: 209-136-7
MDL number: MFCD00003269
Molecular formula: （CH3）8Si4O4 / C8H24O4Si4

Octamethylcyclotetrasiloxane, also called D4, is an organosilicon compound with the formula [(CH3)2SiO]4. 
Octamethylcyclotetrasiloxane is a colorless viscous liquid. 
Octamethylcyclotetrasiloxaneis a common cyclomethicone. 
Octamethylcyclotetrasiloxane is a cyclosiloxane that is the octamethyl derivative of cyclotetrasiloxane. 

Octamethylcyclotetrasiloxaneis an organosilicon compound and a cyclosiloxane. 
Octamethylcyclotetrasiloxane derives from a hydride of a cyclotetrasiloxane.
Octamethylcyclotetrasiloxane is a member of the cyclic siloxane, or cyclomethicone, family. 
Octamethylcyclotetrasiloxane is often called simply D4 because of its four dimethylsiloxane units. 

Octamethylcyclotetrasiloxane exists as an oily liquid or low-melting solid.
Octamethylcyclotetrasiloxane is among the most important of all the cyclic siloxanes, with a global production volume of 136 million kilograms in 1993. 
100,000–1,000,000 tonnes per year of Octamethylcyclotetrasiloxane is manufactured and/or imported in the European Economic Area.

In one the many reactions they reported, they mixed dimethyldichlorosilane1 (Me2SiCl2) with large volumes of water to produce a colorless oil with a composition that had an empirical formula close to that of Me2SiO.
Analysis of the oil showed that Octamethylcyclotetrasiloxane was primarily a mixture of cyclic oligomers of the formula (Me2SiO)x, with isolated compounds ranging from x = 3 to x = 10. 
The relative amounts of each of the cyclosiloxanes varied with hydrolysis conditions such as the Me2SiCl2/H2O ratio and the presence of cosolvents, acids, or bases. 

In general, D4 (x = 4) was the most abundant product.
Today, Octamethylcyclotetrasiloxane is commercially produced by the same general method. 
Octamethylcyclotetrasiloxane's mixture is separated into its components via distillation. 
Octamethylcyclotetrasiloxane and the other oligomers are used to prepare poly(dimethylsiloxane)2 [(Me2SiO)n], familiarly known as silicone oil. 

Octamethylcyclotetrasiloxane is registered under the REACH Regulation and is manufactured in and / or imported to the European Economic Area, at ≥ 10 000 to < 100 000 tonnes per annum.
Octamethylcyclotetrasiloxane is also known as D4. 
Octamethylcyclotetrasiloxane is an odorless, colorless non-oily silicone fluid which has C8H24O4Si4 as chemical formula. 

Octamethylcyclotetrasiloxane is a cyclosiloxane that is the octamethyl derivative of cyclotetrasiloxane. 
Octamethylcyclotetrasiloxane is an organosilicon compound and a cyclosiloxane. 
Octamethylcyclotetrasiloxane derives from a hydride of a cyclotetrasiloxane.
Commercially Octamethylcyclotetrasiloxane is produced from dimethyldichlorosilane. 

Dimethyldichlorosilane is added dropwise to water, the temperature is maintained at 30-40°C, stratified, the acid water is released, the oily material is hydrolyzed with sodium hydroxide solution, the hydrolysate and 0.5%-2% potassium hydroxide are added to the cracking kettle and cracked at 120-140°C and 99.8 kPa vacuum. 
The cracked material is fractionated and the fraction is collected at 173-176°C to obtain octamethylcyclotetraoxysilane.
Octamethylcyclotetrasiloxane (D4) is a volatile methylsiloxane (VMS) with a relatively low molecular weight. 

Octamethylcyclotetrasiloxane has a silicon-oxygen bond in a cyclic arrangement and methyl groups are attached to the silicon atom. 
Octamethylcyclotetrasiloxane, also known as cyclotetrasiloxane.
Octamethylcyclotetrasiloxane is a clear liquid which has C8H24O4Si4 as chemical formula. 

USES and APPLICATIONS of OCTAMETHYLCYCLOTETRASILOXANE:
-Cosmetic Uses:    
*hair conditioning
*skin conditioning
*skin conditioning - emollient solvents

-Octamethylcyclotetrasiloxane  is colorless and insoluble in water, soluble in organic solvents such as stupid. 
The organic silicon polymer, Octamethylcyclotetrasiloxane, which is synthesized by acid base catalysis, is the basic raw material of silicone oil and silicone rubber.
-Octamethylcyclotetrasiloxane itself is used as an additive to plastic and rubber products, paints, adhesives, cosmetics, food packaging, and many other product areas. 

-Octamethylcyclotetrasiloxane's worldwide production is in the hundreds of thousands of tonnes.
-Octamethylcyclotetrasiloxane has faster drying time in low voc formulate in hair sprays
-Octamethylcyclotetrasiloxane is used by consumers, in articles, by professional workers (widespread uses), in formulation or re-packing, at industrial sites and in manufacturing.

-Octamethylcyclotetrasiloxane  is used in the following products: cosmetics and personal care products, washing & cleaning products, polishes and waxes and inks and toners.
-Other release to the environment of this substance is likely to occur from: indoor use (e.g. machine wash liquids/detergents, automotive care products, paints and coating or adhesives, fragrances and air fresheners) and outdoor use.

-Octamethylcyclotetrasiloxane is used as a monomer in the production of silicone polymers and as an intermediate in the production of other organosilicon substances.
-Further Octamethylcyclotetrasiloxane finds its application in electronics, textiles, personal care products and household care products.
-Octamethylcyclotetrasiloxane is a cyclic organic silicon substance  which can be used as monomer in the production of silicone polymers such as rubber, resins and greases.

-Octamethylcyclotetrasiloxane can be used in the manufacture of silicone based polymers for use in medical devices and personal care products.
-Octamethylcyclotetrasiloxane is used to prepare silicone oil, silicone rubber and silicone resin having different degrees of polymerization through ring opening and polymerizing. 
-Octamethylcyclotetrasiloxane is also widely used in various fields viz. construction, electronics, textile, automobile, personal care, food, and machining. 

-Octamethylcyclotetrasiloxane is an organometallic reagent utilized for the preparation of siloxane polymers having high surface-hydrophobicity restoration.
-Octamethylcyclotetrasiloxane, D4 is an industrial product used in many applications, primarly in cosmetic products and polymers, in Octamethylcyclotetrasiloxane's pure form and in mixtures with other siloxanes.  

-Octamethylcyclotetrasiloxane is a cyclic organic silicon substance  which can be used as monomer in the production of silicone polymers such as rubber, resins and greases.
-Octamethylcyclotetrasiloxane is used as a monomer in the production of silicone polymers and as an intermediate in the production of other organosilicon substances. 

-Further Octamethylcyclotetrasiloxane finds its application in electronics, textiles, personal care products and household care products.
-Octamethylcyclotetrasiloxane is widely used in cosmetics.
-Octamethylcyclotetrasiloxane is used to make methyl silicon oils, silicone fluids, and elastomers

-Octamethylcyclotetrasiloxane is also used in a variety of applications including fermentation processes, instant coffee production, paper coatings and sizing, diet soft drinks, waste yeast tanks, food washing solutions, adhesives, textiles, de-asphalting, boiler treatments, detergents, cleaning solutions, surfactants, cosmetic products, and polishes.

-Octamethylcyclotetrasiloxane uses and applications include: Silicone oils; methyl silicone oils; synthesis; reagent; emollient for cosmetics, hair care products, skin care products; antiperspirants and deodorants; cleaning solvent; coupling agent; blocking agent; release agent; lubricant.
-Octamethylcyclotetrasiloxane (D4) is an odorless, colorless non-oily silicone fluid used primarily to make other silicone materials. 
During this manufacturing process, virtually all of the material is consumed, with only a tiny amount of Octamethylcyclotetrasiloxane remaining.

-In a small handful of personal care products, Octamethylcyclotetrasiloxane can be used as an additive providing certain application-related benefits preferred by consumers.
-The cyclic siloxane Octamethylcyclotetrasiloxane and the linear siloxane hexamethyldisiloxane have numerous industrial and consumer applications.

-Synthetic silicon-containing compounds (silicones) are used in a variety of consumer products, e.g., skin care products, antiperspirants, antacids, and antiflatulence agents
-Octamethylcyclotetrasiloxane is a base fluid in a number of personal care products, with excellent spreading and lubrication properties and unique volatility characteristics.

-Octamethylcyclotetrasiloxane can be used in bath oils, deodorants, skin creams, lotions, suntan and shaving products, nail polishes.
-Octamethylcyclotetrasiloxane ’s a basic raw material of silicone oil (modified silicone oil),silicone emulsion,silicone rubber ,silicone resin and other silicone products, and  can also be directly used as  rubber filler treatment agents or  raw material for cosmetics.
-Octamethylcyclotetrasiloxane  is used by consumers in cosmetics and personal care products, washing and cleaning products, polishes and waxes. 

-Octamethylcyclotetrasiloxane is also used in scientific research and development, and Octamethylcyclotetrasiloxane's industrial use includes textile treatment products and dyes. 
-The release of Octamethylcyclotetrasiloxane to the environment is likely to occur from cleaning and personal care products, machine wash liquids/detergents, automotive care products, paints and coating or adhesives, fragrances and air fresheners, either neat or as a byproduct from different silicones.

PRODUCTION AND POLYMERIZATION of OCTAMETHYLCYCLOTETRASILOXANE:
Commercially Octamethylcyclotetrasiloxane is produced from dimethyldichlorosilane. 
Hydrolysis of the dichloride produces a mixture of cyclic dimethylsiloxanes and polydimethylsiloxane. 

From this mixture, the cyclic siloxanes including Octamethylcyclotetrasiloxane can be removed by distillation. 
In the presence of a strong base such as KOH, the polymer/ring mixture is equilibrated, allowing complete conversion to the more volatile cyclic siloxanes:

[(CH3)2SiO]4n → n [(CH3)2SiO]4
Octamethylcyclotetrasiloxane and D5 are also precursors to the polymer. 
The catalyst is again KOH.

POLYDIMETHYLSILOXANE BY THE POLYMERIZATION of OCTAMETHYLCYCLOTETRASILOXANE:
To a resin flask equipped with a thermometer, stirrer, and reflux eondenser is added 1000 gm of octamethylcyclotetrasiloxane. 

The siloxane is heated to 165°C, and then 0.14gm of a potassium hydroxide-isopropanol complex (neutral equivalent = 193.5) is added to give a Si : Κ ratio of 4470:1. In 25 min the stirrer begins to stall, and the polymer is now heated for 3(1/2) hr at 150°C to complete polymerization. 
The resulting polymer has an intrinsic viscosity of 1.5 dl/gm corresponding to a molecular weight of 804,600.

PHYSICAL and CHEMICAL PROPERTIES of OCTAMETHYLCYCLOTETRASILOXANE:
Chemical formula: [(CH3)2SiO]4
Molar mass: 296.616 g·mol−1
Density: 0.956 g/mL
Melting point: 17–18 °C (63–64 °F; 290–291 K)
Boiling point: 175–176 °C (347–349 °F; 448–449 K)
Solubility in water: 56.2±2.5 ppb (23 °C)
log P: 6.98±0.13
Vapor pressure: 124.5±6.2 Pa (25 °C)

Melting point: 17-18℃
Boiling point: 175-176℃
Flash point: 55℃
Relative density: 0.956g/cm³（25℃）
Appearance: Colorless and transparent liquid
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 Ų    
Heavy Atom Count: 16    
Formal Charge: 0    
Complexity: 197    
Isotope Atom Count: 0    

Defined Atom Stereocenter Count: 0    
Undefined Atom Stereocenter Count: 0    
Defined Bond Stereocenter Count: 0    
Undefined Bond Stereocenter Count: 0    
Covalently-Bonded Unit Count: 1    
Compound Is Canonicalized: Yes

Boiling point: 176 °C (1013 hPa)
Density: 0.95 g/cm3 (25 °C)
Explosion limit: 0.4 - 11.7 %(V)
Flash point: 51 °C
Ignition temperature: 400 °C
Melting Point: 18 °C
Vapor pressure: 1.3 hPa (20 °C)
Viscosity kinematic: 1.6 mm2/s (20 °C)
Solubility: <0.001 g/l Hydrolysis

Physical state: liquid
Color: colorless
Odor: weak
Melting point/freezing point:
Melting point/range: 17 - 18 °C - lit.
Initial boiling point and boiling range: 175 - 176 °C - lit.
Flammability (solid, gas): No data available
Upper/lower flammability or explosive limits:
Upper explosion limit: 19,5 %(V) at 1010 hPa

Lower explosion limit: 0,61 %(V) at 1010 hPa
Flash point: 51 °C - closed cup - DIN 51755 Part 1
Autoignition temperature: 384 - 387 °C at 1.013 hPa - ASTM E-659
Decomposition temperature: 313 °C -
pH: No data available
Viscosity 
Viscosity, kinematic: 1,6 mm2/s at 20 °C 
Viscosity, dynamic: No data available

Water solubility: 0,001 g/l at 25 °C - Hydrolysis
Partition coefficient: n-octanol/water:
log Pow: 6,488 at 25,1 °C 
Vapor pressure: 1,3 hPa at 20 °C
Density: 0,956 g/mL at 25 °C - lit.
Relative density: No data available
Relative vapor density: No data available
Particle characteristics: No data available

Explosive properties: No data available
Oxidizing properties: none
Other safety information: No data available
Assay: 95.00 to 100.00
Food Chemicals Codex Listed: No
Specific Gravity: 0.95600 @ 25.00 °C.
Refractive Index: 1.39600 @ 20.00 °C.
Melting Point: 17.50 °C. @ 760.00 mm Hg

Boiling Point: 175.80 °C. @ 760.00 mm Hg
Vapor Pressure: 1.600000 mmHg @ 25.00 °C. (est)
Flash Point: 140.00 °F. TCC ( 60.00 °C. )
logP (o/w): 5.100
Soluble in:
water, 0.005 mg/L @ 25 °C (exp)
water, 0.06124 mg/L @ 25 °C (est)

Melting point: 17-18 °C (lit.)
Boiling point: 175-176 °C (lit.)
Density: 0.956 g/mL at 25 °C (lit.)
vapor density: 1 (vs air)
refractive index: n20/D 1.396(lit.)
Flash point: 140 °F
storage temp.: Store below +30°C.
solubility: <0.001g/l Hydrolysis

form: liquid
Specific Gravity: 0.956
color: colorless
explosive limit: 0.4-11.7%(V)
Water Solubility: INSOLUBLE
Sensitive: Moisture Sensitive
Merck: 14,6747
BRN: 1787074

Min. Purity Spec: 98% (GC)
Physical Form (at 20°C): Low MP Solid or Liquid
Melting Point: 17-18°C
Boiling Point: 175-176°C
Flash Point: 51°C
Density: 0.95
Long-Term Storage: Store long-term in a cool, dry place

FIRST AID MEASURES of OCTAMETHYLCYCLOTETRASILOXANE:
-Description of first-aid measures:
*General advice:
Show this material safety data sheet to the doctor in attendance.

*If inhaled:
After inhalation: 
Fresh air. 
Call in physician.

*In case of skin contact: 
Take off immediately all contaminated clothing. 
Rinse skin with water/ shower. 
Consult a physician.

*In case of eye contact:
After eye contact: 
Rinse out with plenty of water. 
Call in ophthalmologist. 
Remove contact lenses.

*If swallowed:
After swallowing: 
Immediately make victim drink water (two glasses at most). 
Consult a physician.

-Indication of any immediate medical attention and special treatment needed:
No data available

 
ACCIDENTAL RELEASE MEASURES of OCTAMETHYLCYCLOTETRASILOXANE:
-Environmental precautions:
Do not let product enter drains. 

-Methods and materials for containment and cleaning up:
Cover drains. 
Collect, bind, and pump off spills. 
Take up with liquid-absorbent material.
Dispose of properly. 
Clean up affected area.

FIRE FIGHTING MEASURES of OCTAMETHYLCYCLOTETRASILOXANE:
-Extinguishing media:
*Suitable extinguishing media:
Carbon dioxide (CO2) 
Foam 
Dry powder

*Unsuitable extinguishing media:
For this substance/mixture no limitations of extinguishing agents are given.

-Further information:
Prevent fire extinguishing water from contaminating surface water or the ground water system.

EXPOSURE CONTROLS/PERSONAL PROTECTION of OCTAMETHYLCYCLOTETRASILOXANE:
-Control parameters:
--Ingredients with workplace control parameters:
-Exposure controls:
--Personal protective equipment:

*Eye/face protection:
Use Safety glasses

*Skin protection:
Full contact:
Material: Nitrile rubber
Minimum layer thickness: 0,4 mm
Break through time: 480 min

Splash contact:
Material: Nitrile rubber
Minimum layer thickness: 0,11 mm
Break through time: 30 min

-Control of environmental exposure:
Do not let product enter drains. 

HANDLING and STORAGE of OCTAMETHYLCYCLOTETRASILOXANE:
-Precautions for safe handling:
*Advice on protection against fire and explosion:
Take precautionary measures against static discharge.

*Hygiene measures:
Change contaminated clothing. 
Wash hands after working with substance.

-Conditions for safe storage, including any incompatibilities:
*Storage conditions:
Keep container tightly closed in a dry and well-ventilated place. 

STABILITY and REACTIVITY of OCTAMETHYLCYCLOTETRASILOXANE:
-Chemical stability:
The product is chemically stable under standard ambient conditions (room temperature) .

SYNONYMS:
OCTAMETHYLCYCLOTETRASILOXANE
Cyclotetrasiloxane, octamethyl-
2,2,4,4,6,6,8,8-Octamethyl-1,3,5,7,2,4,6,8-tetraoxatetrasilocane
Oktamethylcyklotetrasiloxan
Cyclic dimethylsiloxane tetramer
NUC silicone VS 7207
Oktamethylzyklotetrasiloxan
octamethyl cyclotetrasiloxane
UNII-CZ227117JE
octamethyl-cyclotetrasiloxane
2,2,4,4,6,6,8,8-octamethyl-1,3,5,7,2,4,6,8-tetroxatetrasilocane
CHEBI:25640
CZ227117JE
OMCTS
DSSTox_CID_7205
DSSTox_RID_78349
DSSTox_GSID_27205
Union carbide 7207
Silicone SF 1173
C8H24O4Si4
CCRIS 1327
HSDB 6131
KF 994
NSC 345674
SF 1173
UC 7207
VS 7207
BRN 1787074
volasil(tm) 244
bmse000765
SCHEMBL18354
BIDD:ER0157
Dimethylsiloxane Cyclic Tetramer
CHEMBL1869229
DTXSID7027205
HMMGMWAXVFQUOA-UHFFFAOYSA-
Octamethylcyclotetrasiloxane, 98%
Tox21_201398
Tox21_300547
7595AH
CO9810
NSC345674
AKOS008901191
ZINC169743112
MCULE-2162943570
NSC-345674
NCGC00164099-01
NCGC00164099-02
NCGC00164099-03
NCGC00254406-01
NCGC00258949-01
CS-0213747
FT-0688100
O0142
O9810
Octamethylcyclotetrasiloxane, analytical standard
Cyclotetrasiloxane, 2,2,4,4,6,6,8,8-octamethyl-
octamethyl-1,3,5,7,2,4,6,8-tetraoxatetrasilocane
Q2013804
Cyclotetrasiloxane, 2,2,4,4,6,6,8,8-octamethyl-, homopolymer
2,2,4,4,6,6,8,8-Octamethyl-1,3,5,7,2,4,6,8-tetraoxatetrasilocane 
D4
OMCTS
Cyclotetrasiloxane,octamethyl-
Cyclic tetramer
unioncarbide7207
OCTAMETHYLTETRASILOXANE
Oktamethylcyklotetrasiloxan
Octamethylcyclotetrasiloxane,98%
2-Benzimidazolecarbamic Acid Methyl Ester-d4
2,2,4,4,6,6,8,8-Octamethyl-1,3,5,7,2,4,6,8-tetraoxatetrasilocane
2,2,4,4,6,6,8,8-Octamethylcyclotetrasiloxane
Abil K 4
Cyclic dimethylsiloxane tetramer
D 4
DC 244
DC 344
DC 5258
DWQ 110
DWQ 120; Dabco DC 5258
Dow Corning 244
Dow Corning 244 Fluid
Dow Corning 344
KF 994
LS 8620
Mirasil CM 4
NSC 34567
2,2,4,4,6,6,8,8-Octamethylcyclotetrasiloxane-d24
Octa(methyl-d3)cyclotetrasiloxane
Perdeuteriooctamethylcyclotetrasiloxane
Cyclotetrasilane, octamethyl
Cyclotetrasiloxane, octamethyl
Oktamethylcyklotetrasiloxan
NUC Silicone VS 7207
CO9810
O9810
Octamethyltetrasiloxane
Octamethylcyclotetrasiloxane
Cyclic dimethylsiloxane tetramer
Cyclotetrasiloxane, octamethyl-
Octamethyltetracyclosiloxane