Diethylene glycol, a polyol with the chemical formula C4H10O3, is a colorless, odorless, transparent, hygroscopic viscous liquid with a pungent sweet taste, non-corrosive and low toxicity.

1. Primarily used as a gas dehydrating agent and aromatic hydrocarbon extraction solvent. Also used as a solvent for resins, oils, printing inks, etc., a softening and finishing agent for textiles, and for extracting coumarone and indene from coal tar. Additionally, diethylene glycol is used as a brake fluid additive, celluloid softener, antifreeze, and diluent in emulsion polymerization. It is also used in the production of rubber and plasticizers; polyester resins; fiberglass; polyurethane foam; lubricant viscosity modifiers, etc. Used in the synthesis of unsaturated polyester resins.

2. Used in the synthesis of unsaturated polyester resins, plasticizers, etc. Also used in antifreeze, gas dehydrating agents, plasticizers, solvents, aromatic extraction agents, cigarette humectants, textile lubricants and finishing agents, anti-drying agents for paste and various adhesives, and as a humectant solvent for vat dyes. It is a common solvent for oils, resins, etc.

3. Diethylene glycol is an important raw material in polyurethane synthesis. Polyurethane is an elastic polymer material widely used in furniture, automobiles, construction, textiles, waterproof coatings, adhesives, and other fields. As a soft segment raw material for polyurethane, diethylene glycol improves the flexibility of the material and also acts as a cross-linking agent.

4. Diethylene glycol is used as a solvent and humectant to dissolve dyes, paints, inks, etc., and is an important raw material in the printing, dye, and coating industries. It can also be used as brake fluid, capacitor fluid, and other electrical fluids. In cosmetics and skincare products, diethylene glycol is used as a humectant and emollient to enhance product moisturization and user experience.

5. As an intermediate, diethylene glycol can be used to synthesize other organic compounds, such as surfactants, plasticizers, lubricants, etc. It can also be used in the synthesis of fragrances and pharmaceuticals.

6. In the pesticide field, diethylene glycol can be used to prepare herbicides such as glyphosate.

7. In the pharmaceutical field, it is used to produce various drugs, such as antibiotics and antitumor drugs.

8. In the fuel field, diethylene glycol can be mixed with other compounds to produce renewable energy sources such as biodiesel.

9. In the food industry, diethylene glycol is used as a stabilizer and humectant to help maintain the freshness and taste of food. It is also used as a disinfectant for food packaging materials.