Glycol Ether Producers

Comparative industry trademarks for the glycol ethers and acetates produced by seven manufacturers are detailed in Table 13.1. 

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Diester/Ether Diol of Tetrabromophthalic Anhydride. This material [77098-07-8] is prepared from TBPA in a two-step reaction. First TBPA reacts with diethylene glycol to produce an acid ester. The acid ester and propylene oxide then react to give a diester. The final product, a triol having two primary and one secondary hydroxyl group, is used exclusively as a flame retardant for rigid polyurethane foam (53,54). 

Glycol ethers can be prepared from isopropyl alcohol by reaction of olefin oxides, eg, ethylene oxide [75-21-8] (qv) or propylene oxide [75-56-9] (qv). Reactions such as that to produce 2-isoproxyethanol [109-59-1] (isopropyl CeUosolve) are generally cataly2ed by an alkaU hydroxide. 

This is a particularly troublesome competing reaction when the olefin oxide, eg, ethylene oxide, produces the more reactive terminal primary hydroxy group. Glycol ethers are used as solvents ia lacquers, enamels, and waterborne coatings to improve gloss and flow. 

Glycol Ethers. Glycol ethers are produced by reaction of propylene oxide with various alcohols such as methanol, ethanol, butanol, and phenol. The products are the mono-, di-, and tripropylene glycol ethers. These products are used in protective coatings, inks, textile dyeing, cleaners, antiicing additives for jet fuel, and as chemical intermediates (276). 

Process Raw Material. Industrial solvents are raw materials in some production processes. Eor example, only a small proportion of acetone is used as a solvent, most is used in producing methyl methacrylate and bisphenol A. Alcohols are used in the manufacture of esters and glycol ethers. Diethylenetriamine is also used in the manufacture of curing agents for epoxy resins. Traditionally, chlorinated hydrocarbon solvents have been the starting materials for duorinated hydrocarbon production. 

An explosion and fire (March 13, 1991) occurred at an ethylene oxide unit at Union Carbide Chemicals Plastics Co. s Seadrift plant in Port Lavaca, TX, 125 miles southwest of Houston. The blast killed one, injured 19, and idled the facility, that also produces ethylene, ethylene glycol, glycol ether ethanolamines, and polyethylene. Twenty-five residents were evacuated for several hours as a safety precaution. The plant lost all electrical power, for a few days, because its cogeneration unit was damaged. The Seadrift plant, with 1,600 workers, is capable of making 820 million lb per year of ethylene oxide which is one-third of Carbide s worldwide production of antifreeze, polyester fibers, and surfactants Seadrift produces two thirds of Carbide s worldwide production of polyethylene. 

This reaction is analogous to 10-7. It may be acid (including Lewis acids),base, or alumina catalyzed, occur with electrolysis, and may occur by either an SnI or Sn2 mechanism. Many of the P-hydroxy ethers produced in this way are valuable solvents, for example, diethylene glycol, Cellosolve, and so on. Reaction with thiols leads to hydroxy thioethers. Aziridines can similarly be converted to P-amino ethers. 

Uses. Nearly half the ethyl alcohol produced in petrochemical plants (not the stuff fermented for human consumption) is used as a chemical intermediate in the manufacture of ethyl acrylate, ethyl amines, ethyl acetate (when you pop the cap on nail polish remover, you smell ethyl acetate), ethylene chloride, glycol ethers, acetaldehyde, and acetic acid. However, you will see in the chapters on acetaldehyde and acetic acid, there are now more competitive routes than those based on ethyl alcohol. 

Toxicology. Dipropylene glycol methyl ether (DPGME) at very high concentrations causes narcosis in animals, and it is expected that severe exposure will produce the same effect in humans. Because the propylene glycol ethers are metabolized differently from the ethylene glycol ethers, they are not associated with potent teratogenic, spermatotoxic, or hematopoietic effects. ... 

Uses. Primarily as a chemical intermediate to produce polyether polyols, propylene glycols and propylene glycol ethers fumigant preservative... 

As many as 70 products were at one time produced commercially from ethanol. Some of these downstream products are butanol, 2-ethyl hexanol, crotonaldehyde, butyraldehyde, acetaldehyde, acetic acid, butadiene, sorbic acid, 2-ethylbutanol, ethyl ether, many esters, ethanol-glycol ethers, acetic anhydride, vinyl acetate, ethyl vinyl ether, even ethylene gas. Many of these products are now more economically made from other feedstocks such as ethylene for acetaldehyde and methanol-carbon monoxide for acetic acid. Time will tell when a revival of biologically-oriented processes will offer lower-cost routes to at least the simpler products. 

Allyl polyethylene glycol ethers Non ionic Used to produce surface active, water-soluble silicone ethers (antifoams) ... 

Glycol Ethers. In the same way that water reacts with one or more molecules of ethylene oxide, alcohols react to give monoethers of ethylene glycol, producing monoethers of diethylene glycol, triethylene glycol, and so on, as by-products. 

The solvents most commonly used in paints are glycol ethers, which are known to cause damage to the male reproductive system by destroying the cells that produce sperm in the testes. 

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