Mono propylene glycol (also known as propylene glycol, PG, propan1, 2diol and MPG) is a clear, colourless, and viscous liquid with a characteristic odour. It has the formula C3H8O, is soluble in water, and has hygroscopic properties. MPG is used across a wide range of industries as it has low toxicity, coupled with a freezing point which is depressed upon mixing with water.
Mono propylene glycol is stored and moved in stainless steel or mild steel tanks and can be transported by tank trucks. It is not classified as dangerous for any mode of transport and is not hazardous to health.
There are many uses for mono propylene glycol across many different industries and some chemical manufacturers produce two grades of MPG to meet these varied needs.
The first grade is used in the food, cosmetics, and pharmaceutical industries. MPG is used as a solvent for food colourings and flavourings, and is also a classified humectant food additive (E1520). In the personal care industry it is used as a moisturiser in make-up, shampoo, bubble bath and baby wipes, to name but a few examples. The pharmaceutical industry uses MPG as a solvent in oral, injectable, and topical formulations.
Industrial grade MPG also has a variety of uses but the main application is as an antifreeze and aircraft wing and runway de-icer. This is because the freezing point of MPG lowers upon mixing with water.