Product Identification

Product Name

Phosphorous acid trimethyl ester

Synonyms

Methyl phosphite
Trimethoxyphosphine
Trimethyl ester of phosphorous acid

CAS

121-45-9

Formula

C3H9O3P

Molecular Weight

124.09

EINECS

204-471-5

RTECS

TH1400000

RTECS Class

Reproductive Effector; Primary Irritant

Beilstein/Gmelin

956570

Beilstein Reference

4-01-00-01256

Physical and Chemical Properties

Appearance

A clear colorless liquid with a strong foul odor.

Solubility in water

Very soluble

Melting Point

-77.8

Boiling Point

111

Vapor Pressure

28 (25 C)

Density

1.042 g/cm3 (20 C)

Partition Coefficient

-.93

Heat Of Vaporization

40.6 kJ/mol

Usage

Starting material for vinyl phosphate synth as chemical int, in organic synthesis.

Vapor Density

4.3

Odor threshold

0.1 ppb

Refractive Index

1.4095 (20 C)

First Aid Measures

Ingestion

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.

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 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

Remove contaminated clothing and wash before reuse. Use with adequate ventilation. Ground and bond containers when transferring material. Use spark-proof tools and explosion proof equipment. 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 pressurize, cut, weld, braze, solder, drill, grind, or expose empty containers to heat, sparks or open flames.

Hazards Identification

Inhalation

May cause respiratory tract irritation. 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 skin irritation. 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 irritation of the digestive tract. May cause gastrointestinal irritation with nausea, vomiting and diarrhea. May be harmful if swallowed. Ingestion of large amounts may cause CNS depression.

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.

UN (DOT)

2329

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

Reproductive effects have been reported in animals.

Exposure limit(s)

NIOSH REL: TWA 2 ppm (10 mg/m3)

Poison Class

4

Fire Fighting Measures

Flash Point

27

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. Use water spray to cool fire-exposed containers. Water may be ineffective. Do NOT use straight streams of water.

Fire Potential

HIGHLY FLAMMABLE: Will be easily ignited by heat, sparks or flames.

Accidental Release Measures

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. A vapor suppressing foam may be used to reduce vapors.

Stability and Reactivity

Incompatibilities

Oxidizing agents.

Stability

Stable under normal temperatures and pressures.

Decomposition

Carbon monoxide, oxides of phosphorus, irritating and toxic fumes and gases, carbon dioxide.

Combustion Products

Toxic fumes of POx

Transport Information

UN Number

2329

Hazard Class

3

Packing Group

III