What is Propylene Glycol

1,2-Propanediol is an organic compound with the chemical formula C3H8O2, which is miscible with water, ethanol and various organic solvents. Under normal conditions, it is a colorless viscous liquid, almost tasteless, with a slightly sweet smell. Propylene glycol can be used as a raw material for unsaturated polyester resin, and can be used as a wetting agent in combination with glycerin or sorbitol in cosmetics, toothpaste and soap. In hair dyes, it is used as a humidity control and hair leveling agent, as well as an antifreeze agent, and also used in cellophane, plasticizer and pharmaceutical industry.

What are the properties of propylene glycol?

Flammable liquid. Propylene glycol is hygroscopic and non-corrosive to metals. React with dibasic acid to form polyester. Reacts with nitric acid to form nitrates. It reacts with hydrochloric acid to form chlorohydrins. Heating with dilute sulfuric acid at 170 ° C into propionaldehyde. Oxidation with nitric acid or chromic acid produces glycolic acid, oxalic acid, acetic acid, etc. React with aldehyde to form acetal. Dehydration of 1,2-propanediol produces propylene oxide or polyethylene glycol.

What is propylene glycol used for?

(1) 1,2-Propanediol is an important raw material for unsaturated polyester, epoxy resin, polyurethane resin, plasticizer, and surfactant. The amount used in this area accounts for about 45% of the total consumption of propylene glycol. It is widely used in surface coatings and reinforced plastics.

(2) 1,2-propanediol has good viscosity and hygroscopicity, and is widely used as hygroscopic agent, antifreeze agent, lubricant and solvent in the food, pharmaceutical and cosmetic industries.

• In the food industry, 1,2-propanediol reacts with fatty acids to form propylene glycol fatty acid esters, which are mainly used as food emulsifiers; 1,2-propanediol is an excellent solvent for seasonings and pigments. Due to its low toxicity, it is used as a solvent for spices and food coloring in the food industry.

• 1,2-Propanediol is commonly used in the pharmaceutical industry as a solvent, softener and excipient in the manufacture of various ointments and ointments, and in the pharmaceutical industry as a solvent for blending agents, preservatives, ointments, vitamins, penicillin, etc. .

• Since propylene glycol has good miscibility with various spices, it is also used as a solvent and softener for cosmetics, etc.

• 1,2-Propanediol is also used as a tobacco moisturizer, antifungal agent, food processing equipment lubricant and solvent for food marking inks. Aqueous solutions of 1,2-propanediol are effective antifreeze agents. It is also used as tobacco wetting agent, antifungal agent, fruit ripening preservative, antifreeze and heat carrier, etc.

Although propylene glycol does not spontaneously ignite, it is combustible. Long-term storage does not deteriorate, but the opening absorbs moisture. Storage and transportation containers should be made of galvanized iron drums, aluminum or stainless steel. Avoid contact with water and humid environment. Storage tanks must be kept clean, dry and free from rust.