Hexamethyldisilane

  • Permethyldisilane
Formula
(CH3)3SiSi(CH3)3
Structure
Description
Colorless liquid.

Registry Numbers and Inventories.
CAS
1450-14-2
EC (EINECS/ELINCS)
215-911-0
EC Class
highly flammable, irritant, sensitizing
S 16 29 33
RTECS
JM9170000
RTECS class
Other
UN (DOT)
1993
Beilstein/Gmelin
1633463
Beilstein Reference
4-04-00-04277
Canada DSL/NDSL
NDSL
US TSCA
Listed
Austrailia AICS
Listed
New Zealand
Listed
Japan ENCS (MITI)
Listed

Properties.
Formula
C6H18Si2
Formula mass
146.38
Melting point, °C
13 - 15
Boiling point, °C
112
Vapor pressure, mmHg
23 (20 C)
Density
0.729 g/cm3 (20 C)
Solubility in water
Insoluble
Refractive index
1.4229 (20 C)
Partition coefficient, pKow
2.50
Heat of fusion
3.02 kJ/mol
Heat of vaporization
37.4 kJ/mol

Hazards and Protection.
Storage
Keep away from heat, sparks, and flame. Keep away from sources of ignition. Store in a tightly closed container. Store in a cool, dry, well-ventilated area away from incompatible substances. Flammables-area.
Handling
Wash thoroughly after handling. Use only in a well ventilated area. Ground and bond containers when transferring material. Use spark-proof tools and explosion proof equipment. Avoid breathing dust, vapor, mist, or gas. Avoid contact with skin and eyes. Empty containers retain product residue, (liquid and/or vapor), and can be dangerous. Avoid contact with heat, sparks and flame. Do not pressurize, cut, weld, braze, solder, drill, grind, or expose empty containers to heat, sparks or open flames.
Protection
Eyes: Wear appropriate protective eyeglasses or chemical safety goggles as described by OSHA's eye and face protection regulations in 29 CFR 1910.133 or European Standard EN166. Skin: Wear appropriate protective gloves to prevent skin exposure. Clothing: Wear a chemical apron. Wear appropriate protective clothing to prevent skin exposure.
Respirators
Wear a NIOSH/MSHA or European Standard EN 149 approved full-facepiece airline respirator in the positive pressure mode with emergency escape provisions. Follow the OSHA respirator regulations found in 29CFR 1910.134 or European Standard EN 149. Always use a NIOSH or European Standard EN 149 approved respirator when necessary.
Small spills/leaks
Absorb spill with inert material, (e.g., dry sand or earth), then place into a chemical waste container. Clean up spills immediately, using the appropriate protective equipment. Remove all sources of ignition. Use a spark-proof tool. A vapor suppressing foam may be used to reduce vapors.
Disposal code
1
Stability
Stable under normal temperatures and pressures.
Incompatibilities
Strong oxidizing agents.
Decomposition
Carbon monoxide, irritating and toxic fumes and gases, carbon dioxide, silicon oxide.

Fire.
Flash Point,°C
11
Fire fighting
Wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. Will burn if involved in a fire. Use water spray to keep fire-exposed containers cool. Containers may explode in the heat of a fire. Extinguishing media: For small fires, use dry chemical, carbon dioxide, water spray or alcohol-resistant foam. For large fires, use water spray, fog, or alcohol-resistant foam. Use water spray to cool fire-exposed containers. Water may be ineffective. Use agent most appropriate to extinguish fire. Do NOT use straight streams of water.
Fire potential
HIGHLY FLAMMABLE: Will be easily ignited by heat, sparks or flames.
Hazards
Vapors may form explosive mixtures with air. Vapors may travel to source of ignition and flash back. Most vapors are heavier than air. They will spread along ground and collect in low or confined areas (sewers, basements, tanks). Vapor explosion hazard indoors, outdoors or in sewers.
Combustion products
Fire may produce irritating, corrosive and/or toxic gases.

Health.
Exposure effects
   Ingestion
May cause gastrointestinal irritation with nausea, vomiting and diarrhea. The toxicological properties of this substance have not been fully investigated.
   Inhalation
May cause respiratory tract irritation. The toxicological properties of this substance have not been fully investigated. Vapors may cause dizziness or suffocation.
   Skin
May cause skin irritation.
   Eyes
May cause eye irritation.

First aid
 
   Ingestion
Never give anything by mouth to an unconscious person. Do NOT induce vomiting. If conscious and alert, rinse mouth and drink 2-4 cupfuls of milk or water.
   Inhalation
Remove from exposure to fresh air immediately. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. Get medical aid if cough or other symptoms appear.
   Skin
Flush skin with plenty of soap and water for at least 15 minutes while removing contaminated clothing and shoes. Get medical aid if irritation develops or persists. Wash clothing before reuse.
   Eyes
Flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids. Get medical aid.

Transport.
UN number
1993
Response guide
Hazard class
3
Packing Group
I; II; III
 
HS Code
2931 00 95