Octamethylcyclotetrasiloxane , >98.0%(GC) , 556-67-2
Synonym(s):
Octamethylcyclotetrasiloxane;Octamethyltetrasiloxane
CAS NO.：556-67-2
Empirical Formula: C8H24O4Si4
Molecular Weight: 296.62
MDL number: MFCD00003269
EINECS: 209-136-7
| Pack Size | Price | Stock | Quantity |
| 5ML | RMB23.20 | In Stock |
|
| 25ML | RMB25.60 | In Stock |
|
| 100ML | RMB39.20 | In Stock |
|
| 500ML | RMB71.20 | In Stock |
|
| 2.5L | RMB286.40 | In Stock |
|
| 10L | RMB841.60 | In Stock |
|
| others | Enquire |
PRODUCT Properties
| 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) |
| vapor pressure | 1.32hPa at 25℃ |
| refractive index | n |
| Flash point: | 140 °F |
| storage temp. | Store below +30°C. |
| solubility | <0.001g/l Hydrolysis |
| form | liquid |
| color | colorless |
| Specific Gravity | 0.956 |
| explosive limit | 0.4-11.7%(V) |
| Water Solubility | INSOLUBLE |
| Sensitive | Moisture Sensitive |
| Merck | 14,6747 |
| BRN | 1787074 |
| Dielectric constant | 2.4（20℃） |
| InChIKey | HMMGMWAXVFQUOA-UHFFFAOYSA-N |
| LogP | 6.98 at 21.7℃ |
| CAS DataBase Reference | 556-67-2(CAS DataBase Reference) |
| NIST Chemistry Reference | Cyclotetrasiloxane, octamethyl-(556-67-2) |
| EPA Substance Registry System | Octamethylcyclotetrasiloxane (556-67-2) |
Description and Uses
Octamethylcyclotetrasiloxane is used as a monomer in the production of silicone polymers and as an intermediate in the production of other organosilicon substances.Further it finds its application in electronics, textiles, personal care products and household care products.
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.
Safety
| Symbol(GHS) |    GHS02,GHS08,GHS09 |
| Signal word | Warning |
| Hazard statements | H226-H361f-H410 |
| Precautionary statements | P202-P210-P233-P240-P273-P308+P313 |
| Hazard Codes | Xn |
| Risk Statements | 53-62-10 |
| Safety Statements | 36/37-46-51-61 |
| RIDADR | UN 1993 3/PG 3 |
| WGK Germany | 1 |
| RTECS | GZ4397000 |
| TSCA | Yes |
| HazardClass | 3 |
| PackingGroup | III |
| HS Code | 29319090 |
| Hazardous Substances Data | 556-67-2(Hazardous Substances Data) |
| Toxicity | LD50 oral in rat: 1540mg/kg |
