Provenance

Reference data from EU CLP Annex VI and published regulations — verify against your supplier's SDS before use.

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Substance profile

Ethyleneimine

Ethyleneimine is an oily, water-white liquid with a pungent, ammonia-like odor.

CAS 151-56-4 C2H5N 43.07 g/mol Danger

01 · Identification

What Ethyleneimine is

Ethyleneimine is an oily, water-white liquid with a pungent, ammonia-like odor. Its molecular formula is C2H5N and its molecular weight is 43.07 g/mol. It boils at 56.1 °C, melts at -71.5 °C.

Under the GHS it carries the signal word Danger. It is classed as hazardous Air Pollutants (HAPs).

CAS number151-56-4
EC number205-793-9
Index number613-001-00-1
Molecular formulaC2H5N
Molecular weight43.07 g/mol
Chemical class Hazardous Air Pollutants (HAPs)

Other names for Ethyleneimine

  • aziridine

02 · GHS classification

Hazards and label elements

Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.

Signal wordDanger
Hazard statements assigned to Ethyleneimine
CodeHazard statement
H225 Highly flammable liquid and vapour.
H350 May cause cancer <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H340 May cause genetic defects <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H310 Fatal in contact with skin.
H330 Fatal if inhaled.
H300 Fatal if swallowed.
H314 Causes severe skin burns and eye damage.
H411 Toxic to aquatic life with long lasting effects.

Precautionary statements: P201, P210, P233, P241, P242, P260, P270, P271, P273, P280, P301, P302, P304, P308, P310, P313, P330, P331, P352, P391, P403, P501

03 · Physical and chemical properties

Ethyleneimine properties

Every value is shown with the conditions it was measured under and the source it came from. Where sources disagree, all values are listed rather than one being picked — the difference is usually a different form of the substance, not an error.

Property Value Conditions Source
Boiling point 56.11 °C (133 °F) NIOSH
56 °C (132.8 °F) at 760 mmHg DOE PAC
Melting point -71.5 °C (-96.7 °F) HSDB
-71.67 °C (-97 °F) NIOSH
-72.22 °C (-98 °F) CAMEO
Density 0.83 g/cm³ NIOSH
0.8321 g/cm³ at 24 °C HSDB
0.8321 g/cm³ at 20 °C CAMEO
Solubility SOL IN ALKALI HSDB
Soluble in ethanol; slightly soluble in ether; very soluble in chloroform; miscible in organic solvents HSDB
In water, 1X10+6 mg/L (miscible) HSDB
Vapor pressure 160 mmHg NIOSH
160 mmHg at 20 °C CAMEO
213 mmHg at 25 °C HSDB
Flash point -11.11 °C (12 °F) HSDB
Autoignition temperature 320 °C (608 °F) HSDB
322 °C (611.6 °F) ICSC
Lower explosive limit (LEL) 3.3 % by volume HSDB
3.6 % by volume CAMEO
Upper explosive limit (UEL) 54.8 % by volume HSDB
46 % by volume CAMEO
Vapor density 1.48 (air = 1) HSDB
1.5 (air = 1) ICSC
Odor threshold Perceptible level of odor: 2 ppm HSDB
3.5 mg/ cu m = 1.96 ppm; abs perception limit 2ppm HSDB
Odor Threshold Low: 2.0 [ppm] Haz-Map
Corrosivity Corrosive HSDB

Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.

04 · Handling and storage

Storing and handling Ethyleneimine

Storage conditions

Can be stored for some time over a few pellets of sodium hydroxide. /In a closed container/

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

/Aziridine/ gives the explosive 1-chloroazidine on treatment with /chlorinating agents/ eg sodium hypochlorite solution.

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

ETHYLENEIMINE vapors are not inhibited and may form polymers in vents or flame arresters, resulting in stopping of the vents. Produces toxic oxides of nitrogen during combustion. Reacts with sodium hypochlorite and other chlorinating agents to give the explosive compound 1-chloroazidine. Decomposes if heated under pressure. or else hazardous polymerization may occur. Incompatible with silver or aluminum, which induce polymerization May polymerize explosively upon contact with acids. Polymerization is catalyzed by carbon dioxide [EPA, 1998].

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check Ethyleneimine in the storage compatibility matrix →

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