Diethylene glycol (DEG) is an organic compound with the formula (HOCH2CH2)2O. It is a colorless, practically odorless, poisonous, hygroscopic liquid with a sweetish taste. It is miscible in water, alcohol, ether, acetone, and ethylene glycol. DEG is a widely used solvent.
Diethylene glycol is similar in properties to MEG (mono ethylene glycol), but DEG has a higher boiling point, viscosity, and specific gravity. MEG is the raw material used in the production of polyester fiber, PET resins, alkyds, and unsaturated polyesters. Diethylene glycol is used in the manufacture of unsaturated polyester resins, polyurethanes and plasticizers. It is a water-soluble liquid; boiling point 245 C, and is soluble in many organic solvents.
DEG is produced by the partial hydrolysis of ethylene oxide. Depending on the conditions, varying amounts of DEG and related glycols are produced. The resulting product is two ethylene glycol molecules joined by an ether bond, Diethylene glycol is derived as a co-product with ethylene glycol and triethylene glycol.