1,1,3,3-Tetramethyldisiloxane

  • 1,1,3,3-Tetramethyl-1,3-disiloxane
  • 1,1,3,3-Tetramethyl-1,3-dihydrodisiloxane
  • Bis(dimethylsilyl) oxide
  • Bis(dimethylsilyl) ether
  • Dimethylsilyl ether
  • sym-Tetramethyldisiloxane
Formula
(CH3)2SiH)2O
Structure
Description
Colorless liquid.

Registry Numbers and Inventories.
CAS
3277-26-7
EC (EINECS/ELINCS)
221-906-4
EC Class
highly flammable
S 16 23 29 33
RTECS
JN1000000
RTECS class
Other
UN (DOT)
1993
Beilstein/Gmelin
1733364
Beilstein Reference
4-04-00-03991
Canada DSL/NDSL
NDSL
US TSCA
Listed
Austrailia AICS
Listed
New Zealand
Listed
Japan ENCS (MITI)
Listed

Properties.
Formula
C4H14OSi2
Formula mass
134.33
Boiling point, °C
71
Vapor pressure, mmHg
138 (25 C)
Vapor density (air=1)
4.6
Density
0.7555 g/cm3 (20 C)
Solubility in water
Insoluble
Refractive index
1.3700 (20 C)
Partition coefficient, pKow
4.12
Heat of vaporization
30.4 kJ/mol

Hazards and Protection.
Storage
Keep away from sources of ignition. Store in a tightly closed container. Keep under a nitrogen blanket. Store in a cool, dry, well-ventilated area away from incompatible substances. Flammables-area. Store protected from moisture.
Handling
Wash thoroughly after handling. 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 eyes, skin, and clothing. Empty containers retain product residue, (liquid and/or vapor), and can be dangerous. Keep container tightly closed. Avoid contact with heat, sparks and flame. Avoid ingestion and inhalation. Do not allow contact with water. Use only in a chemical fume hood. Do not pressurize, cut, weld, braze, solder, drill, grind, or expose empty containers to heat, sparks or open flames. Keep from contact with moist air and steam.
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 appropriate protective clothing to prevent skin exposure.
Respirators
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. Avoid runoff into storm sewers and ditches which lead to waterways. Clean up spills immediately, using the appropriate protective equipment. Remove all sources of ignition. Use a spark-proof tool. Provide ventilation. Do not get water inside containers. A vapor suppressing foam may be used to reduce vapors.
Disposal code
24
Stability
Stable under normal temperatures and pressures.
Incompatibilities
Moisture, strong acids, strong bases, strong oxidizing agents.
Decomposition
Carbon monoxide, irritating and toxic fumes and gases, carbon dioxide, silicon oxide.

Fire.
Flash Point,°C
-3
Autoignition, °C
240
Fire fighting
Wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. During a fire, irritating and highly toxic gases may be generated by thermal decomposition or combustion. 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. Runoff from fire control or dilution water may cause pollution. Runoff to sewer may create fire or explosion hazard. Extinguishing media: Use water spray to cool fire-exposed containers. Water may be ineffective. Do NOT get water inside containers. Do NOT use straight streams of water. For large fires, use water spray, fog or regular foam. For small fires, use dry chemical, carbon dioxide, or alcohol resistant foam.
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
1
 
Flammability
4
 
 
Reactivity
0
 

Health.
Exposure effects
Effects may be delayed.
   Ingestion
May cause gastrointestinal irritation with nausea, vomiting and diarrhea. May cause cardiac disturbances. Ingestion of large amounts may cause CNS depression.
   Inhalation
May cause respiratory tract irritation. Aspiration may lead to pulmonary edema. Vapors may cause dizziness or suffocation. May cause cardiac abnormalities. May cause burning sensation in the chest.
   Skin
May cause irritation and dermatitis. May cause cyanosis of the extremities.
   Eyes
May cause eye irritation. May cause chemical conjunctivitis and corneal damage.

First aid
 
   Ingestion
Never give anything by mouth to an unconscious person. Get medical aid. 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 breathing is difficult, give oxygen. Get medical aid. DO NOT use mouth-to-mouth respiration. If breathing has ceased apply artificial respiration using oxygen and a suitable mechanical device such as a bag and a mask.
   Skin
Get medical aid. Flush skin with plenty of soap and water for at least 15 minutes while removing contaminated clothing and shoes. Wash clothing before reuse.
   Eyes
Immediately 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