Silicones & Silicates
REACH
Phenyltris(trimethylsiloxy)silane
CAS Number
2116-84-9
EC Number
218-320-6
What is Phenyltris(trimethylsiloxy)silane?
Phenyltris(trimethylsiloxy)silane (CAS 2116-84-9), also known as Tris(trimethylsiloxy)phenylsilane, is a phenyl-functional silicone fluid.
Where is Phenyltris(trimethylsiloxy)silane used?
- Personal care: lightweight, non-greasy carrier fluid in skin and hair formulations, improving spreadability and dry, silky after-feel
- Coatings: enhances surface wetting and gloss where conventional silicone fluids underperform optically
- High-temperature lubricants: base fluid or additive where thermal resistance beyond standard silicone oils is required
- Adhesive and sealant manufacturing: processing aid or reactive diluent to adjust viscosity and surface adhesion
- The phenyl substitution raises refractive index compatibility and thermal stability relative to standard dimethyl silicones.
Commercial specifications
- Technical and cosmetic grades; cosmetic grade meets purity requirements for personal care
- Packaging from small laboratory quantities through drum and IBC volumes
Other Names (Synonyms)
Tris(trimethylsiloxy)phenylsilane|1,1,1,5,5,5-Hexamethyl-3-phenyl-3-(trimethylsilyloxy)trisiloxane|RefChem:1051654|trimethyl-[phenyl-bis(trimethylsilyloxy)silyl]oxysilane|Trisiloxane, 1,1,1,5,5,5-hexamethyl-3-phenyl-3-[(trimethylsilyl)oxy]-|Trisiloxane, 1,1,1,5,5,5-hexamethyl-3-phenyl-3-(trimethylsiloxy)-|Dow Corning 556
What are the physical properties of Phenyltris(trimethylsiloxy)silane?
Melting Point -102 °C
Boiling Point 264-266 °C
Density 0.924 g/cm³
Flash Point 127°C
Color Colorless to Almost colorless
Form clear liquid
Water Solubility 6.6μg/L at 23℃
Vapor Pressure 0.09Pa at 25℃
Refractive Index n 20/D 1.437
Log P 9 at 20℃
How is Phenyltris(trimethylsiloxy)silane classified and handled safely? Learn More
Danger
GHS06· Toxic GHS07· Irritant
Hazard Statements
H315 Causes skin irritation
H319 Causes serious eye irritation
H330 Fatal if inhaled
H335 May cause respiratory irritation
Precautionary Statements
P260 Do not breathe dust/fume/gas/mist/vapours/spray.
P261 Avoid breathing dust/fume/gas/mist/vapours/spray.
P264 Wash … thoroughly after handling.
P271 Use only outdoors or in a well-ventilated area.
Which trade and regulatory codes apply to Phenyltris(trimethylsiloxy)silane?
HS Code 2931.90.9010
WGK (Germany) 1