Cyclic tetramer of dimethylsiloxane, supplied as a monomer rather than a finished fluid. Undergoes ring-opening polymerization to build linear polydimethylsiloxane chains, making it a starting intermediate for silicone fluid and elastomer production.
Product Code
ASIL-D4
Octamethylcyclotetrasiloxane (D4)
CAS Number
556-67-2
EINECS
209-136-7
Description
Synonyms
Key applications
- Ring-opening polymerization to polydimethylsiloxane
- Intermediate for silicone fluid and elastomer manufacture
- Siloxane chain-building monomer
Characteristics
| Family | Cyclic Siloxanes |
|---|---|
| Molecular formula | C8H24O4Si4 |
| Molecular weight | 296.62 g/mol |
| Melting point | 17-18 °C |
| Boiling point | 175-176 °C |
| Density at 25°C | 0.956 g/cm³ |
| Refractive index at 20°C | 1.396 |
| Flash point | 55°C (closed cup) |
| Appearance | Colorless oily liquid |