Triethyl phosphate (TEP) CAS No.78-40-4, is an organophosphorus compound with the chemical formula (C₂H₅O)₃PO. It is a colorless, odorless liquid used primarily as a flame retardant, plasticizer, and solvent. TEP’s versatility and stability make it a valuable chemical in various industrial applications, from plastics to pharmaceuticals.

Key Properties of Triethyl phosphate (TEP) 

  • Chemical Formula: (C₂H₅O)₃PO

  • CAS Number: 78-40-4

  • Molecular Weight: 182.15 g/mol

  • Appearance: Colorless, transparent liquid

  • Solubility: Soluble in water, alcohol, and most organic solvents

  • Boiling Point: 215–216°C

  • Density: 1.072 g/cm³

  • Stability: Chemically stable under normal conditions

These properties enable TEP to function effectively in diverse applications.

Applications of Triethyl phosphate (TEP) CAS No.78-40-4

1. Flame Retardant

TEP is widely used as a flame retardant in:

  • Plastics and resins: Enhances fire resistance in polyurethane, polyester, and epoxy resins.

  • Textiles: Applied to fabrics to meet fire safety standards in upholstery and clothing.

2. Plasticizer

TEP serves as a plasticizer in:

  • Polymer manufacturing: Improves flexibility and durability in plastics like cellulose acetate and nitrocellulose.

  • Coatings and adhesives: Enhances workability and performance in paints and sealants.

3. Solvent and Chemical Intermediate

  • Solvent: Used in industrial processes for dissolving resins, gums, and other organic compounds.

  • Chemical synthesis: Acts as an intermediate in the production of pesticides, pharmaceuticals, and other chemicals.

4. Other Industrial Uses

  • Catalysts: Employed as a catalyst or stabilizer in chemical reactions.

  • Lubricants: Used in high-temperature lubricants to improve performance.

  • Pharmaceuticals: Serves as a component in certain drug formulations.

Frequently Asked Questions (FAQs)-Triethyl phosphate (TEP) 

1. What is Triethyl Phosphate(TEP) mainly used for?

TEP is used as a flame retardant, solvent, plasticizer, and chemical intermediate in coatings, plastics, pharmaceuticals, and industrial synthesis.

2. Is Triethyl Phosphate safe?

It is considered low-toxicity and is widely used in industrial and controlled applications. Safety guidelines and MSDS are provided upon request.

3. Can TEP be used in high-temperature applications?

Yes. TEP has excellent thermal stability, making it suitable for heat-resistant coatings and engineering plastics.

4. What purity grades do you supply?

Available grades include:

  • 99% industrial grade

  • 99.5% high purity

  • Low-acid grade for sensitive formulations

5. Is TEP compatible with PVC and polyurethane?

Yes. TEP is a highly compatible plasticizer for PVC and a flame retardant additive in polyurethane foams.

6. Do you provide COA, TDS, and MSDS?

Yes. Full documentation is available upon request.

7. What packaging options are available?

We offer 200kg steel drums, 1000kg IBC totes, and ISO tank containers for bulk shipments.