Diethylene glycol

Diethylene glycol (CAS 111-46-6), commonly sourced as DEG, is a hygroscopic diol used in industrial manufacturing as a solvent, plasticizer and chemical intermediate.

Where is Diethylene glycol used?

• Polyester resin and polyurethane: monomer or co-monomer influencing flexibility and softness of the finished polymer
• Natural gas processing: dehydration agent removing water vapour from gas streams before pipeline transmission
• Textile and leather finishing: softening agent improving hand-feel and workability
• Printing ink and packaging adhesives: solvent and humectant controlling viscosity and preventing premature drying
• It also serves as a carrier and processing aid where slower evaporation is commercially advantageous.
• Lowers the freezing point of water-based systems, providing stability in industrial heat transfer fluids and antifreeze formulations.
• Main active component in grinding aid formulations for cement clinker grinding, improving mill efficiency and reducing energy costs.
• As a plasticizer, provides a uniform finish and performs well at low temperatures.
• Used as a selective solvent for aromatics in petroleum refining.

Formulation notes

• Incompatible with strong bases.
• Immiscible with benzene, toluene, animal or vegetable oils, cellulose ethers, chlorinated rubbers and polyvinyl chloride (PVC).

Typical specification

• Supplied with a minimum purity of 99.5% (GC method).
• Maximum water content of 0.2% (Karl Fischer method).
• Maximum color value of 10 Pt-Co (ASTM D1209).

Regulatory status

• Supplies include REACH documentation where applicable.
• The EMA questions and answers on DEG/EG contamination are part of the EU GMP guide annexes, specifically Annex 8 on supplementary requirements.
• The EMA added three new questions and answers to its EU GMP guidance to address the risk of contamination of glycerin and other excipients with diethylene glycol and ethylene glycol.
• The EMA recommends treating glycerin, propylene glycol and certain macrogols as high-risk materials requiring careful supplier oversight and testing according to the respective pharmacopoeia monograph.

Storage, packaging and handling

• Stainless steel, aluminum or epoxy-coated tanks are the most suitable for storage.
• Should be stored protected from moisture in original sealed packaging or closed tanks.

Frequently asked questions about Diethylene glycol

In which lubricant applications is diethylene glycol used?

It is used as a solvent and viscosity regulator in the lubricant industry, optimizing lubricant performance and extending the service life of machines and lubricated parts.

Technical content is compiled and updated by the SoleChem product team from public technical sources; the certificate of analysis (COA) governs product-specific specifications.