Propanediol

Propanediol is a diol, meaning it is an organic compound containing two hydroxyl groups. It exists in three structural isomers: 1,1-propanediol, 1,2-propanediol, and 1,3-propanediol. 1,2-propanediol, also known as propylene glycol, is the most common isomer and is widely used in various industrial and consumer applications.

1,2-propanediol is a clear, colorless, and viscous liquid with a faint, sweet odor. It is miscible with water and many organic solvents. Its properties make it useful as a solvent, humectant, and preservative. It is found in food products, cosmetics, pharmaceuticals, and antifreeze. In the food industry, it is designated as E1520 and is used as a solvent for flavors and colors.

1,3-propanediol is another significant isomer. It can be produced through petroleum-based routes or via bio-based fermentation processes using renewable resources like corn sugar. This bio-based production has gained traction due to its sustainability advantages. 1,3-propanediol is primarily used as a monomer in the production of polymers, such as polytrimethylene terephthalate (PTT), which is used in textiles and carpets.

The safety and environmental impact of propanediol isomers vary depending on the specific isomer and its application. 1,2-propanediol is generally considered safe for use in food and cosmetic products by regulatory agencies. The environmental profile of 1,3-propanediol is often favored when produced from renewable sources, offering a more sustainable alternative in polymer manufacturing.