Solubility in waterfully miscible Solubility in ethanolfully miscible Solubility in diethyl etherfully miscible Solubility in acetonefully miscible Solubility in chloroformfully miscible Thermal conductivity: 0.34 W/m-K (50% H2O @ 90 ° C (194 ° F))
Applications 45% of propylene glycol produced is used as chemical feedstock for the production of unsaturated polyester resins. In this regard, propylene glycol reacts with a mixture of unsaturated maleic anhydride and isophthalic acid to give a copolymer. This partially unsaturated polymer undergoes further crosslinking to yield thermoset plastics. Related to this application, propylene glycol reacts with propylene oxide to give oligomers and polymers that are used to produce polyurethanes.
Propylene glycol is considered Generally Recognized As Safe by the U. S. Food and Drug Administration, and it is used as an humectant (E1520), solvent, and preservative in food and for tobacco products, as well as being the major ingredient in the liquid used in electronic cigarettes (along with vegetable glycerine and, more rarely, PEG 400). It is also used in pharmaceutical and personal care products. Propylene glycol is a solvent in many pharmaceuticals, including oral, injectable and topical formulations, that are insoluble in water, use propylene glycol as a solvent in their clinical, injectable forms.
Like ethylene glycol, propylene glycol is able to lower the melting point of water, and so it is used as aircraft de-icing fluid. It is similarly used as automotive antifreeze. Propylene glycol is a minor ingredient in the oil dispersant Corexit, used in great quantities during the Deepwater Horizon oil spill