Product Identification

Product Name

Hexamethylcyclotrisiloxane

Synonyms

2,2,4,4,6,6-Hexamethyl-1,3,5,2,4,6-trioxatrisilinane
Cyclotrisiloxane, hexamethyl
Dimethylsiloxane cyclic trimer
Hexamethyltrisiloxane
LS 8120
SDK 10

CAS

541-05-9

Formula

C6H18O3Si3

Molecular Weight

222.46

EINECS

208-765-4

Beilstein/Gmelin

5676485

Physical and Chemical Properties

Appearance

Colorless to white crystals.

Solubility in water

May decompose.

Melting Point

64.5

Boiling Point

134

Vapor Pressure

4.2 (24 C)

Density

1.12 g/cm3 (20C)

Partition Coefficient

4.47

Heat Of Vaporization

39.8 kJ/mol

Heat Of Combustion

-5891 kJ/mol

Vapor Density

8

First Aid Measures

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 not breathing, give artificial respiration. If breathing is difficult, give oxygen. Get medical aid. DO NOT use mouth-to-mouth respiration.

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

Flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids. Get medical aid.

Handling and Storage

Storage

Keep away from sources of ignition. Store in a tightly closed container. Store in a cool, dry, well-ventilated area away from incompatible substances. Keep away from water. Store protected from moisture.

Handling

Wash thoroughly after handling. Remove contaminated clothing and wash before reuse. Use with adequate ventilation. Ground and bond containers when transferring material. Avoid contact with eyes, skin, and clothing. Empty containers retain product residue, (liquid and/or vapor), and can be dangerous. Avoid contact with heat, sparks and flame. Avoid ingestion and inhalation. Do not allow contact with water. 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.

Hazards Identification

Inhalation

The toxicological properties of this substance have not been fully investigated. Aspiration may lead to pulmonary edema. Vapors may cause dizziness or suffocation. 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.

Ingestion

May cause gastrointestinal irritation with nausea, vomiting and diarrhea. The toxicological properties of this substance have not been fully investigated. Ingestion of large amounts may cause CNS depression.

Hazards

Water Reactive. Material will react with water and may release a flammable and/or toxic gas. Do NOT use water directly on fire.

EC Risk Phrase

R 11

EC Safety Phrase

S 16 22 24/25

UN (DOT)

1325

Exposure Controls/Personal Protection

Personal 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

A respiratory protection program that meets OSHA's 29 CFR 1910.134 and ANSI Z88.2 requirements or European Standard EN 149 must be followed whenever workplace conditions warrant a respirator's use.

Exposure Effects

Effects may be delayed.

Fire Fighting Measures

Flash Point

32

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. 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. Do NOT use water directly on fire. Use water spray to cool fire-exposed containers. Do NOT get water inside containers.

Lower exp. limit

1.1

Fire Potential

Flammable/combustible material. May be ignited by friction, heat, sparks or flames.

Accidental Release Measures

Small spills/leaks

Vacuum or sweep up material and place into a suitable disposal container. Clean up spills immediately, using the appropriate protective equipment. Avoid generating dusty conditions. Remove all sources of ignition. Use a spark-proof tool. Provide ventilation. Do not get water inside containers.

Stability and Reactivity

Incompatibilities

Moisture.

Stability

Stable under normal temperatures and pressures.

Decomposition

Carbon monoxide, irritating and toxic fumes and gases, carbon dioxide, silicon oxide.

Combustion Products

Fire may produce irritating and/or toxic gases.

Transport Information

UN Number

1325

Hazard Class

4.1

Packing Group

II; III