Glycol

Ethylene glycol is a colourless, odourless, involatile and hygroscopic liquid with a sweet taste. It is somewhat viscous liquid; miscible with water; boiling point 198 C, melting point 13 C; soluble in ethanol, acetone, acetic acid, glycerine, pyridine, aldehydes; slightly soluble in ether; insoluble in oil, fat, hydrocarbones. It is prepared commercially by oxidation of ethylene at high temperature in the presence of silver oxide catalyst, followed by hydration of ethylene oxide to yield mono-, with di-, tri-, and tetraethylene glycols as co-products. The yields of ethylene glycol are depending on pH conditions. The acid-catalyzed condition in the presence of excess water provides the highest yield of monoethylene glycol. Because of its low freezing point, involatility and low corrosive activity, it is widely used in mixtures of automobile antifreeze and engine-cooling liquids. Ethylene glycol has become increasingly important in the plastics industry for the manufacture of polyester fibers and resins, including polyethylene terephthalate, which is used to make plastic bottles for soft drinks (PET bottles). MEG is the raw material in the production of polyester fiber, PET resins, alkyd and unsaturated polyester. Diethylene glycol, CH2OHCH2OCH2CH2OH, is similar in properties to MEG, but with a higher boiling point, viscosity.

Properties of Butyl Glycol: