Propylene glycol, also known as 1,2-propanediol, is a colorless, transparent, viscous liquid with hygroscopicity. It can react with acids to form esters and with alkyl sulfates or halogenated hydrocarbons to form ethers. Miscible in water, acetone, ethyl acetate, and chloroform, soluble in ether. Soluble essential oils, but not miscible with petroleum ether and paraffin. It is more stable to heat and light, and more stable at low temperatures. Industrial grade propylene glycol has a slight spicy taste. Propylene glycol can be classified into industrial grade, food grade, and pharmaceutical grade according to its use. The main application proportion is: manufacturing unsaturated polyester resin accounts for 27%; Food, medicine, and cosmetics account for 20%; Functional fluids (antifreeze, deicing agent, heat transfer fluid) account for 20%; Liquid detergent accounts for 17%; Paint and coatings account for 5%; Tobacco moisturizer accounts for 2%; Other uses include plasticizers accounting for 9%.
Propylene glycol
Application of propylene glycol
1. Propylene glycol is an important raw material for the production of unsaturated polyester, epoxy resin, polyurethane resin, plasticizer, and surfactant.
2. Used as a plasticizer and ink additive for alkyd resins.
3. Propylene glycol has excellent bactericidal and wetting properties, and can be miscible with many substances. It is a solvent for oils, paraffin, resins, dyes, etc., used as a wetting agent and dissolving agent in advanced antifreeze.
4. In the coating industry, propylene glycol has the characteristics of low freezing point and the ability to mix with water in any proportion. When mixed with water, it can greatly reduce the overall freezing point of the coating and enhance its frost resistance. Therefore, it is often used as an antifreeze in coatings, which can prevent the coating from freezing at 0 degrees Celsius. Due to its good compatibility with water and other solvents, high boiling point, it is easy to reach equilibrium in water-based coating systems, and can also provide fluidity and slow drying of coatings.
5. Antifreeze used for aircraft.
6. Excellent solvents for various spices, pigments, and preservatives in the food industry; Extraction solvents for vanilla beans, roasted curry granules, natural spices, etc; Moisturizing and softening agents for candies, bread, packaged meat, etc.
7. The tobacco industry uses it as a moisturizer.
8. Used for producing food emulsifier propylene glycol ester (main varieties include propylene glycol monostearate, propylene glycol monooleate, and propylene glycol monolaurate).
9. It can be used as a stabilizer, coagulant, anti hydrolysis agent, etc. in pastries, as well as a softener and emulsifier for gum based candies.
10. Fruit ripening preservatives.
11. Pharmaceutical grade propylene glycol can be directly used as excipients and reaction materials.
①. Directly used as auxiliary material:
Used as a solvent in the pharmaceutical industry for the production of injection solutions, eye drops, oral liquids, disinfectants, washings, ointments, etc;
Propylene glycol can be used as a solvent and softener for cosmetics. It can be found in almost all forms of cosmetics, hair care products, lotion, post shaving care products, deodorants, mouthwashes, and toothpaste. It is generally used as a wetting agent in cosmetics, toothpaste, and soap in combination with glycerol or sorbitol. Used as a moisture regulating and hair smoothing agent in hair dye.
②. Used as a reaction material:
Production of essence cyclohexanone 1,2-propanediol ketal, butanone 1,2-propanediol ketal, citral 1,2-propanediol acetal, benzaldehyde 1,2-propanediol acetal, etc.