(also aziridine), a colorless, mobile liquid with the odor of ammonia.
Ethyleneimine has the structural formula
It has a boiling point of 56.7°C, a melting point of – 73.9°C, and a density of 0.837 g/cm3 at 20°C. Readily soluble in water, it also dissolves in most organic solvents. Ethyleneimine is produced by reacting ethanolamine with sulfuric acid and then treating with a base the resulting sulfuric acid ester; it can also be produced by the action of bases on 2-bromoethylamine.
Ethyleneimine is highly toxic; the maximum permissible concentration of its vapors in the air is 0.02 mg/m3. In the liquid phase, ethyleneimine is very damaging to the skin. Both ethyleneimine and its derivatives have mutagenic properties. Several of these derivatives—including triethylenephosphoramide and thiotriethylenephosphoramide—are used in medicine (as alkylating antineoplastics), and in agricultural, microbiological selection. Polyethyleneimine (the polymer of ethyleneimine) has a low toxicity and is used as an auxiliary agent for various purposes—for example, to increase the strength of rubber and paper or purify waste waters.