Ethylene amine, as a basic fatty amine, has been widely used in the domestic market as a curing agent for epoxy resins through modification.

The characteristics of ethylene amine used as a curing agent for epoxy resin:

• Ethylene amine is a low viscosity liquid that can be well mixed with epoxy resin;

• Ethylene amine can be cured at room temperature, making the process convenient;

• The multifunctional amino group in ethylamine has no steric hindrance and high reactivity;

• The exothermic reaction of ethylamine can accelerate the curing rate.

The main products of ethylene amine:

Ethylenediamine is the main reactant in the production process of ethylenediamine. English abbreviation: EDA Molecular formula: H2N-C2H4-NH2 approximate molecular weight:~60 Active hydrogen equivalent:~15 Theoretical dosage for reaction with epoxy resin: 6-8 parts

Diethylenetriamine is a typical representative of ethylene amines. Abbreviation: DETA Molecular formula: H2N (C2H4NH) 2H Approximately molecular weight:~103 Active hydrogen equivalent:~20.6 Theoretical dosage for reaction with epoxy resin: 8-11 parts

Triethylenetetramine is also a widely used room temperature curing agent in epoxy resins. English abbreviation: TETA Molecular formula: H2N (C2H4NH) 3H Approximately molecular weight:~146 Active hydrogen equivalent:~24.3 Theoretical dosage for reaction with epoxy resin: 10-13 parts

Tetraethylenepentamine is also a widely used room temperature curing agent in epoxy resins. English abbreviation: TEPA Molecular formula: H2N (C2H4NH) 4H Approximately molecular weight:~189 Active hydrogen equivalent:~27 Theoretical dosage for reaction with epoxy resin: 11-15 parts

Polyethylenepolyamines are reaction mixtures in the production process of ethylene amines. Molecular formula: H2N (C2H4NH) nH reacts with epoxy resin Theoretical dosage: 14-15 parts

The cured product of ethylene amine and epoxy resin has excellent adhesion, corrosion resistance, and mechanical strength. However, due to the low molecular weight, low viscosity, and low vapor pressure of ethylamine, it is prone to corrosion during the reaction process, which is not friendly to operators and the environment. Ethylene amine itself has a strong ammonia taste and high moisture absorption, leading to whitening and carbonization reactions. It needs to be modified to be well applied.

After modification, the following properties of ethylene amine have been improved:

  1. Extend the operational time appropriately;  

  2. Accelerate or reduce the curing reaction rate (slow down the heat release of the reaction); 

  3. Improve its compatibility with epoxy resin; 

  4. Reduce the reaction between free amines and carbon dioxide in the air; 

  5. Reduce toxicity, volatility, and skin irritation; 

  6. Prepare a simple dosage ratio to reduce dosage errors.

Application fields of ethylene amine as epoxy resin curing agent:

The epoxy resin curing agent modified with ethylene amine can be widely used in various adhesives, sealants, small castings, laminated materials, and room temperature curing coatings.