Polyethylene polyamine

　　Main Applications

　　Epoxy Resin Curing Agents

　　This is the most significant application field. Low molecular weight polyethylene polyamines (such as diethylenetriamine, triethylenetetramine) are commonly used room temperature/medium temperature curing agents. They achieve resin cross-linking and curing through the ring-opening reaction between amino groups and epoxy groups. Different varieties have different effects on the properties after curing:

　　Low molecular weight varieties (such as DETA, TETA) cure quickly, but the cured products are relatively brittle;

　　High molecular weight varieties (such as TEPA, PEHA) cure more slowly, have a longer pot life, and the cured products exhibit better flexibility and higher impact strength. They are widely used in coatings, adhesives, composite materials, electronic encapsulation, and other fields.

　　Chelating Agents and Metal Treatment

　　Utilizing the strong chelating ability of multiple amino groups towards metal ions, they can remove heavy metals from industrial wastewater (such as Cu2+, Ni2+, Hg2+), or be used for the extraction and recovery of precious metals (such as gold, platinum).

　　Used as additives in the electroplating industry to improve the uniformity and gloss of the coating, and enhance the adhesion between the coating and the substrate.

　　Used in boiler water treatment to chelate calcium and magnesium ions in the water, preventing scale formation.

　　Organic Synthesis Intermediates

　　Synthesize polymer materials such as polyamide resins (e.g., intermediates for polyamide-66), polyimides, and imidazolines. These materials are used as high-temperature resistant insulating materials in the aerospace and electronics fields.

　　Prepare cationic surfactants, used as softeners and antistatic agents in the textile industry, or as additives in oilfield drilling fluids (filtration reduction, viscosity enhancement).

　　Synthesize corrosion inhibitors by forming a protective film through adsorption on the metal surface, used for anti-corrosion in oil pipelines and steel equipment.

　　Other Applications

　　Gas Purification: Absorb acidic gases (H2S, CO2) from natural gas and syngas. The amino groups react with acidic gases to form salts, achieving desulfurization and decarbonization.

　　Paper Industry: Used as wet strength agents and sizing agents to improve paper strength and water resistance.

　　Pesticides and Pharmaceuticals: Used as intermediates for synthesizing insecticides and fungicides, or as amination reagents in pharmaceutical synthesis.