Product Introduction
Industrial - grade propylene glycol has the chemical formula C_3H_8O_2. Under normal conditions, it appears as a colorless, viscous liquid. It is nearly odorless, with a faintly sweet smell upon close inspection, and has hygroscopic properties.
Physical Properties: Its density is 1.0361 g/cm^3 at 20℃, the melting point is -59.5℃, the boiling point is 187.3℃, and the refractive index is 1.4329. It can be miscible with a variety of organic solvents such as water, ethanol, ether, chloroform, and acetone.
Chemical Properties: It can undergo reactions such as substitution, esterification, condensation, and dehydration. It can react with oxygen - containing inorganic acids to form inorganic acid esters, and react with aldehydes to form acetals. It does not corrode metals.
Production Methods: The main production methods include the propylene oxide hydration method and the transesterification method. There is also an innovative "Hydrogen Peroxide to Propylene Glycol" (HPPG) process jointly developed by Evonik and Dow, which directly synthesizes propylene glycol from propylene and hydrogen peroxide.
Application Areas: It is an important raw material for the production of unsaturated polyesters, epoxy resins, polyurethane resins, plasticizers, and surfactants. It can also be used as a plasticizer for alkyd resins, an ink additive, an antifreeze in the paint industry, and for the antifreeze of aircraft.
Advantages
• Superior Performance: It has excellent solubility and stability, and can be miscible with a wide range of substances. It can dissolve essential oils, fats, paraffins, resins, dyes, etc. It has a low freezing point, and when mixed with water, it can lower the freezing point of coatings and other products, enhancing their antifreeze performance. Its good viscosity and hygroscopicity help maintain the moisture content of products.
• Mature Production Process: For example, the transesterification method has advantages such as low cost, mature technology, mild reaction conditions, low equipment investment, and high production safety. New production processes like the HPPG process have made breakthroughs in cost - effectiveness, energy conservation, environmental protection, and production capacity improvement.
• Widely Used: It has important applications in multiple industrial fields. As a key raw material for many chemical products, it has a large market demand and broad application prospects.
• High Safety: It has low toxicity and little irritation, is relatively safe for humans and the environment, and is not classified as a hazardous chemical. It has high safety during use, transportation, and storage.