MEG
ETHYLENE GLYCOL/EG is shortname of MEG/ MONOETHYLENE GLYCOL.
EG is a clolorless, practically odorless, low-volatile, hygroscopic liquid. It is completely miscible with water and many organic liquids.
The low volatility and low molecular weight of ethyleen glycol, coupled with low solvent action on automobile finishes, make EG an ideal base for all winter automobile antifreeze.
Asphalt emulsion paints are protected from freezing by the addition of EG; freezing of these emulsions would break the suspension. Carbon dioxide pressure type fire extinguishers and wet sprinkler systems often contain EG to prevent freeze ups.
Aqueous EG solutions are used as heat transfer solutions at low termperatures and at elevated temperatures. As low temperature coolants in refrigeration systems, aqueous solutions of EG are less corrosive than brine. As a high temperature coolant, aqueous solutions of EG find application in electronic tubes.
Most applications involving ethylene glycol for anti freeze and coolant used require specially inhibited EG.
EG is used in brake and shock absorber fluids to help dissolve inhibitors, counteract rubber swelling, and inhibit foam formation.
Mixtures of glycerol and EG are nnitrated in the presence of sulfuric acid to form solutions of nitroglycerine in EG dinitrate. These solutions are used in the manufacture of low freezing dynamite. EG dinitrate is the explosive ingredient that depresses the feezing point and makes dynamite safer to handle in cold weather.
Polyester resins based on maleic and phthalic anhydrides, EG, and vinyl type monomers are important in the low pressure laminating of glass fibers, asbestos, cloth, and paper.
Polyester glass fiber laminates are used in making furniture, suitcases, boat hulls, aircraft parts, and automobile bodies.
EG reacts with dibasic acids to form alkyd type resins. These resins are of interest to modify synthetic rubbers, in adhesives, and in other applications. Alkyds made from EG and Phytalic anhydride are used with similar resins based on glycerol or pentaerythritol in the manufacture of surface coatings.
Polyester fibers and films are made from the condensation product of EG and Dimethyl Terepthhalate or terephtalic acid. Polyester fibers have had the most dramatic growth of all synthetic fibers. The textile industry concensus is that polyester fiber is ideally suited to satisfy customer demand for a medium priced fiber with " ease of care " and durability properties. It is also being used in tire cord, carpeting, and other industrial end use areas.
Rosin esters of EG are plasticizers in adhesives, laquers, and enamels. EGis readily esterified with mono and di carboxylic acids to yield solvents, resins and plasticizers.
Water dispersions of urea formaldehyde and melamine formaldehyde are stabilized against gel formation and viscocity changes by the use of EG.
Hight purity of EG ( Iron and chloride free ) is a solvent and suspending medium for ammonium perborate, the conductor in practically all electrolytic capacitors. EG is used in these capacitors because it is relatively non volatile, non corrosive to aluminium, and has excellent electrical properties.
Capacitors are essential parts in electric motors, radios, and other electronic equipment.
EG is a humectant for textile fibers, paper, leather, adhesives, and glue. It used helps make these products softer, more pliable, and more durable. EG is about one and one half times as hygroscopic as glycerol at normal room temperatures and humidities.
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