Silicones & Silicates
REACH
Octamethyltrisiloxane
CAS Number
107-51-7
EC Number
203-497-4
What is Octamethyltrisiloxane?
Octamethyltrisiloxane (CAS 107-51-7) is a low-viscosity linear silicone fluid used as a carrier solvent, surface modifier, and lubricant.
Where is Octamethyltrisiloxane used?
- Personal care: lightweight carrier for active ingredients in skin serums and hair conditioning products
- Antiperspirants and cosmetic blends: improves spreadability and skin feel
- Textile and leather finishing: imparts softness, water repellency, and surface slip
- Metalworking and automotive lubricants: base fluid or co-solvent
- It supports emulsification and dispersion where silicone-based wetting agents are needed.
Commercial specifications
- Cosmetic grade meets purity standards for personal care and sensitive formulations
- Packaging ranges from drums to IBC containers, with bulk supply for industrial volumes
Other Names (Synonyms)
Trisiloxane, octamethyl-|1,1,1,3,3,5,5,5-Octamethyltrisiloxane|dimethyl-bis(trimethylsilyloxy)silane|Pentamethyl(trimethylsilyloxy)disiloxane|Dimethylbis(trimethylsiloxy)silane|9G1ZW13R0G|Pentamethyl(trimethylsiloxy)disiloxane|Trisiloxane, 1,1,1,3,3,5,5,5-octamethyl-
What are the physical properties of Octamethyltrisiloxane?
Melting Point -80 °C
Boiling Point 152-153 °C
Density 0.820 g/cm³
Flash Point 99 °F
Appearance clear colourless liquid
Color Colourless to Pale Yellow
Form liquid
Water Solubility 34μg/L at 23℃
Vapor Pressure 5.3hPa at 25℃
Refractive Index n 20/D 1.384(lit.)
Log P 6.6 at 25.3℃
How is Octamethyltrisiloxane classified and handled safely? Learn More
Warning
GHS02· Flammable
Hazard Statements
H226 Flammable liquid and vapor
H413 May cause long lasting harmful effects to aquatic life
Precautionary Statements
P210 Keep away from heat, hot surfaces, sparks, open flames and other ignition sources. No smoking.
P233 Keep container tightly closed.
P240 Ground and bond container and receiving equipment.
P241 Use explosion-proof [electrical/ventilating/lighting/…] equipment.
Which trade and regulatory codes apply to Octamethyltrisiloxane?
HS Code 29319090
UN Number 1993
ADR Class 3
Packing Group III
Storage Class 3 - Flammable liquids
WGK (Germany) 3