The scientific name of propylene glycol is “1,2-propylene glycol”. The chemical formula is CH3CHOHCH2OH. The molecular weight is 76.10. There is a chiral carbon atom in the molecule. The racemic body is a hygroscopic viscous liquid with a slightly spicy taste. The specific gravity is 1.036 (25/4℃), and the freezing point is -59℃. The boiling point is 188.2℃, 83.2℃ (1,333 Pa), Chemicalbook is miscible in water, acetone, ethyl acetate and chloroform, and soluble in ether. It can be dissolved in many essential oils, but it is immiscible with petroleum ether, paraffin and grease. It is relatively stable to heat and light, and more stable at low temperatures. The boiling point of the left-handed body is 187~189℃, and the specific rotation [α] D20-15.0°. Propylene glycol can be oxidized to propionaldehyde, lactic acid, pyruvic acid and acetic acid at high temperatures.