Product Identification
【Product Name】Diethyl hydrogen phosphonate
【Synonyms】Diethyl phosphite   亚磷酸二乙酯
【CAS】762-04-9
【Formula】C4H11O3P
【Molecular Weight】138.12
【EINECS】212-091-6
【RTECS】TG7875000
【RTECS Class】Other
【Beilstein/Gmelin】605759
【Beilstein Reference】4-01-00-01329

Physical and Chemical Properties
【Appearance】Clear, colorless liquid.
【Solubility in water】Soluble
【Boiling Point】50℃
【Vapor Pressure】<2℃
【Density】1.093 g/cm3 (0℃)
【Heat Of Vaporization】38.10 kJ/mol
【Usage】Textile finishing agent, antioxidant, additive for adhesives & for extreme pressure lubricant, chemical intermediate for organic phosphorus compounds.
【Refractive Index】1.4057 (18.4℃)

First Aid Measures
【Ingestion】Do NOT induce vomiting. Allow the victim to rinse his mouth and then to drink 2-4 cupfuls of water, and seek medical advice.
【Inhalation】Remove from exposure to fresh air immediately.
【Skin】Flush skin with plenty of soap and water for at least 15 minutes while removing contaminated clothing and shoes.
【Eyes】Irrigate exposed eyes with copious amounts of tepid water for at least 15 minutes. If irritation, pain, swelling, lacrimation, or photophobia persist, the patient should be seen in a health care facility.

Handling and Storage
【Storage】Store in a cool, dry place. Keep container closed when not in use.
【Handling】Wash thoroughly after handling. Remove contaminated clothing and wash before reuse. Avoid contact with eyes, skin, and clothing. Avoid ingestion and inhalation.

Hazards Identification
【Inhalation】Harmful by inhalation.
【Skin】Irritating. Harmful on contact with the skin.
【Hazards】During a fire, irritating and highly toxic gases may be generated by thermal decomposition or combustion.

Exposure Controls/Personal Protection
【Personal Protection】Wear appropriate safety ggles, protective clothing and gloves.
【Respirators】Wear a NIOSH/MSHA or European Standard EN 149 approved full-facepiece airline respirator in the positive pressure mode with emergency escape provisions.
【Exposure Effects】The toxological properties of this substance have not been fully investigated.
【Poison Class】5

Fire Fighting Measures
【Flash Point】90℃
【Fire Fighting】Wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. In case of fire, use water, dry chemical, chemical foam, or alcohol-resistant foam.

Accidental Release Measures
【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.

Stability and Reactivity
【Stability】Stable under normal temperatures and pressures.
【Incompatibilities】Strong oxidizing agents - moist air or water - strong bases - strong acids - acid chlorides.
【Decomposition】Phosphine, carbon monoxide, oxides of phosphorus, irritating and toxic fumes and gases, carbon dioxide.