Propylene Glycol's General Information

Propylene glycol, or propane-1,2-diol in IUPAC nomenclature, is an organic double alcohol. It has a chemical formula of C₃H₈O₂ and a CAS number of 57-55-6. It is a thick, clear, and nearly odorless substance with a faintly sweet taste. Propylene glycol is similar in characteristics with glycerin - hygroscopic, soluble with water, acetone, and chloroform.

Manufacture

Propylene glycol is usually sourced from propylene oxide. Production is more or less similar with glycerin, using either catalytic (150°-180°C) or non-catalytic high-temperature process (200°-220°C). the process is manufactured using ion exchange resin or a small amount of sulfuric acid or alkali. Final products include 20% propylene glycol, 1.5% dipropylene glycol, and other polypropylene glycols. Glycerol can be converted from propylene glycol as well.

Usage

Propylene glycol serves as humectant and preservative for various food products. It is mixed in snacks, pastries, soda drinks, and ice cream. It serves as cooling agent for alcoholic beverages and further extends freezing time for food. Likewise, propylene glycol is used as a solvent for different medical preparations like oral, injectable, and topical formulations. As a humectant, it is labeled as E1520. Sunscreens, shampoos, make-ups, creams, deodorants, and other toiletry items contain this versatile alcohol as well. Its hygroscopic property makes it a suitable moisturizer for toothpaste, mouth wash, and cigarettes. Propylene glycol serves as a carrier for perfume oils and soap bases. 

Industrially, propylene glycol is used as antifreeze for water systems and heaters because it is less toxic. Moreover, it is added to other household items like furniture polish and glass cleaners. Photographic chemicals use propylene glycol as a solvent.

Propylene glycol

Chemicals Direct purchases USP Propylene Glycol which can be used directly in food and medicine. If your application does not require USP, our pure 99.9% propylene glycol is perfect for your application. Glycol is commonly used as a safe to use antifreeze. Glycol is very soluble in water, just dilute to your required freeze protection. These are two main type of propylene glycol, Technical Grade and USP Grade.

Labeling a product or a substance as USP implies that it conforms to all the legal requirements of the FDA and that it was produced in accordance with the principles outlined in FDA’s Good Manufacturing Practices (GMP). Many other nations also have compiled an official national pharmacopeia, similar in scope and content to the USP. Currently, there is a collaborative international program to harmonize the glycerin monographs in the USP and in the European Pharmacopeia.

Propylene glycol is a colorless, odorless, and a viscous liquid that is derived from natural gas and the bio diesel market. Glycol is completely safe when used properly. USP Propylene Glycol is used in food flavorings, cake mixes, salad dressings, popcorn, soft drinks, popcorn, ice cream and sour cream. It also protects food from freezing and helps as a preservative. Applications include: toiletries, lotions, creams, baby wipes, shampoos, lubricants, antiperspirants, cosmetics, lipstick, cleaners, room deodorizers, sanitizers and non-toxic antifreezes, soap making and as a carrier in fragrance oils.