Also found in: Dictionary, Thesaurus, Medical.



acyclic compounds containing two hydroxyl groups. The simplest glycol (ethylene glycol, HOCH2— CH2OH) and other lower glycols are viscous, colorless liquids, readily soluble in water and alcohol, and sweet to the taste. The higher glycols are solids that are readily soluble in alcohol and ether and less readily soluble in water. Depending on the relative arrangement of the OH groups in the molecule, a distinction is made among the 1,2-glycols, such as Glycols the 1,3-glycols, such as Glycols; and so on. Glycols containing two OH groups at the same carbon atom—for example, chloral hydrate, CCl3CH(OH)2—are stable only in the presence of strong electronegative groups.

In their chemical properties, glycols resemble the monohydric alcohols in many respects (they form alkoxides, ethers, esters, and other compounds). Depending on the relative arrangement of the OH group in the molecule and on the dehydration conditions, dehydration of glycols may yield carbonyl compounds or cyclic ethers. Thus, ethylene glycol yields acetaldehyde or 1,4-dioxane, whereas 1,4-butane diol yields tetrahydrofuran.

A general synthetic method for glycols is the hydrolysis of the corresponding dihalides (I) or chlorohydrins (II); 1,2-glycols are also prepared by the hydration of the corresponding epoxides (III) or by the oxidation of olefins (IV):

The 1,2-glycols and their derivatives have the greatest practical importance. The esters of higher glycols are used as plasticizers.

References in periodicals archive ?
The Ethylene Glycol production is part of Sasol's US Mega Project, including a 1.
Some areas have regulations regarding the use and disposal of particular glycols and antifreeze solutions, concerning things such as ground structure, the water table and drainage.
Browse the full Monoethylene Glycol (MEG) Market for Polyethylene Terephthalate (PET), Polyester Fiber, Coolant & Antifreeze and Other Applications- Growth, Share, Opportunities, Competitive Analysis, and Forecast 2015 - 2021 report at http://www.
Whether any limits should be applied to the levels of propylene glycol and glycerol in personal lubricant formulations
The manufacturer of glycols, Dow Chemical Canada, is one of our nation's older companies, being founded in 1942 as a subsidiary of The Dow Chemical Company Midland, Mich.
The agency also believes the organisational changes would not affect Petronas' commitment to Optimal Glycols and Optimal Chemicals.
Ester-based plasticizers include benzoates, isophthalates, adipates, phthalates, citrates, trimellitates and various glycol esters of aliphatic acids.
Some water-based inks used in package printing contain glycol ethers and considerable levels of residual monomers.
9) Know regulatory requirements for the use and disposal of glycols.
Polyesters which are hydroxy terminated result from stepgrowth polymerization of adipic acid and an excess of a low molecular weight glycol (ethylene glycol, butanediol, hexanediol).
Water glycol fluid is composed of polyglycol thickener, glycol (ethylene, diethylene, and propylene), water, and additives.