Diethylenetriamine (DETA) is a trifunctional aliphatic amine (triamine) appearing as a colorless to pale-yellow liquid with a strong ammonia-like odor.
It serves as an epoxy curing agent, chelating agent, and acid gas absorber, making it a key raw material in resin, gas treatment, and specialty chemical industries.

Chemical Structure

Molecular Formula: C₄H₁₃N₃
Molecular Weight: 103.17 g/mol
Structural Formula: (NH₂–CH₂–CH₂)₂–NH
IUPAC Name: N′-(2-aminoethyl)ethane-1,2-diamine
Chemical Family: Polyamines

Typical Physical and Chemical Properties

Property	Specification
Appearance	Clear to light-yellow liquid
Odor	Strong, ammonia-like
Boiling Point	207–208 °C
Flash Point (closed cup)	94–98 °C
Density (20 °C)	~0.955 g/cm³
Viscosity (25 °C)	~2 mPa·s
Refractive Index (nD 20 °C)	1.474–1.476
pH (1% solution)	11.5–12.0
Water Solubility	Completely miscible
Hygroscopicity	Absorbs moisture from air

Advantages

High reactivity with epoxy resins, enabling rapid and efficient curing
Functions as a tridentate ligand in metal coordination chemistry
Excellent CO₂ and H₂S absorption capacity for gas sweetening applications
Highly water-soluble and compatible with polar solvents
Economical and widely available in industrial grades

Limitations

Strongly corrosive to skin, eyes, and respiratory tissues
Hygroscopic – requires moisture-proof packaging and handling
May oxidize and discolor on exposure to air and light
Heavier-than-air vapors may accumulate in low areas, posing inhalation risks
Pungent odor can limit use in enclosed environments

Main Applications

Epoxy resin and adhesive systems: curing agent for coatings, composites, and adhesives
Coordination chemistry: ligand for forming complexes (e.g., [Co(dien)(NO₂)₃])
Oil & gas industry: absorption of CO₂ and H₂S in gas treatment units
Additive manufacturing: corrosion inhibitor and lubricant additive
Polymer chemistry: precursor for polyamides, polyimides, and specialty resins

Safety and Handling

UN Number: 2079 Hazard Class: 8 (Corrosive) Packing Group: II

GHS Classification:
⚠️ Signal Word: DANGER

Hazard Statements:

H302: Harmful if swallowed
H312: Harmful in contact with skin
H314: Causes severe skin burns and eye damage
H317: May cause allergic skin reaction
H334: May cause respiratory sensitization

Recommended PPE:

Nitrile or butyl rubber gloves
Chemical-resistant goggles or face shield
Protective clothing
Respirator or air filtration system in enclosed spaces

Storage Conditions:

Store in tightly closed, corrosion-resistant containers
Keep in a cool, dry, well-ventilated area (preferably below 15 °C)
Avoid contact with strong acids, oxidizing agents, and moisture
Protect from heat and direct sunlight

Summary

Diethylenetriamine (DETA) is a highly reactive, multifunctional amine widely used in epoxy resin curing, gas absorption, and chelation chemistry.
It offers excellent reactivity, solubility, and cost-effectiveness — provided it is handled under controlled, corrosion-safe, and well-ventilated conditions.