Glycol ethers and their esters

This is a very broad group containing monomeric and polymeric compoimds which may be classified as plasticizers or, in some cases, as slow evaporating solvents. The following chemical formulas describe stmctures of these materials  

Main acids used in commercial products acetic, mixed (average Cg), caprylic (octanoic), 2-ethylhexyl, capric (decanoic)  

Highly recommended for these polymers PVC, PVAc, PVB, PU, NBR, SBR, CR, CTA, EPDM, EVA, acrylics, cellulose derivatives, polyesters  

Main fields of application electronic applications, cable coatings, printing inks, pharmaceuticals, cosmetics, floor tiles, paints, coatings, automotive, glues  

---

Properties R-Co 100 max. color low odor dilutable with alcohols, aromatic hydrocarbons, glycol ethers and their esters limited diluent tolerance for min. spirit, turpentine dens. 1.0 g/cm (20 C) vise. 0.34).5 Pa s (23 C) acid no. 2 max. flash pt. 14 C 59-62% NV Storage 12 mos shelf life if kept cool (but away from frost) in tightly sealed drums or storage tanks Plastopal EBS 100B [BASFAG]... 

Properties Pt-Co 100 max. color dilutable with alcohols, aromatic hydrocarbons, glycol ethers and their esters limited diluent tolerance for min. 

Preservation of artifacts with poly(alkylene glycol)s and their esters and ethers was first patented by Mo och Domsjo AB (4). The patent document, naming Moren and Centerwall as inventors of the method, was dated the September 30, 1953, to be sealed as of the 10th of October 1952 (4). 

Scholz, H. J., Suehler, H., Quack, J. M., Schuler, W. and Trautmann, M., Process for the preparation of carboxylic esters of alkylene glycol ethers and their utilization, European Patent Application 89105 357.1, to Hoechst AG (1989) Chem. Abstr., 112, 181911. 

Fermentation-derived organic acids and their esters are potentially important chemical feedstocks for polymers and specialty polymers, but most significantly as alternative solvents for industrial and consumer applications. For example, lactate esters are derived from renewable carbohydrate raw materials such as cornstarch. They exhibit much lower toxicity compared with halogenated hydrocarbons and ethylene glycol ethers and are environmentally benign. Some studies suggested that lactate ester solvents have the potential of replacing petroleum-based solvents... 

The copolymerization between trioxane and suitable comonomers (ethylene oxide, 1,3-dioxolane, diethylene glycol formal, 1,4-butane diol formal in amounts of 2-5% by weight) is performed using cationic initiators. The cationic initiators could be Lewis acids, such as BF3 or its etherate BF3Bu20 which was used, for example by Celanese (the mechanism of this reaction was studied in detail [163,164]) or protic acids such as perchloric acid, perfluoroalkane sulfonic acids and their esters and anhydrides. Heteropoly acids were used and also a series of carbenium, oxocarbenium salts, onium compounds, and metal chelates. To regulate the molecular weight chain-transfer agents, such as methylal and butylal, are added. 

Unsubstituted and Heat Reactive. The first class, the unsubstituted, heat-reactive resins, are made by using phenol, cresols, and xylenols. They are multifunctional and thus can be cross-linked to form films. They are soluble in alcohols, ketones, esters, and glycol ethers and insoluble in aromatic and aliphatic hydrocarbons. They will tolerate some water in their solvents and, in some cases, are completely water soluble. They are compatible with polar resins such as amino resins, epoxies, polyamides, and poly(vinyl butyral), though compatibility on curing is dependent on reaction between the two resins. Less polar resins such as alkyds and drying oils are incompatible. 

Their acetate esters are also used. Ethylene glycol-based ether-alcohols and their esters are now less used on account of their toxicity, being replaced by the propylene glycol versions. 

This comprehensive reference book examines the physical and chemical properties, uses, and toxicity of organic solvents in the chemical and related process industries. It will afford the chemist, chemical engineer, researchers, and other workers in the chemical and allied industries the opportunity to review all the important chemical and physical properties of industrial solvents. The current environmental impact of recommended safe handling procedures and chemical reactivity solvents are also presented. The solvents are classified according to their chemical structure and include aldehydes, aliphatic and aromatic hydrocarbons, ethers, halogenated hydrocarbons, ketones, nitroparaffins, and monohydric and polyhydric alcohols. Also covered are acids, aliphatic and heterocyclic amines, esters, glycol ethers, and several miscellaneous solvents. 

Oxygenated solvents - The principal oxygenated solvents for coatings are ketones, esters, glycol ethers, and alcohols. These are high purity synthetic compounds as opposed to the hydrocarbons, which are naturally derived chemical mixtures. The oxygenated solvents also offer much stronger solvency and partial to complete water miscibility. They are widely used as the active solvents for synthetic binders because of their ability to be blended to provide tailored solvency and evaporation rate. 

Glycols and their ethers undergo violent decomposition in contact with 70% perchloric acid. This seems likely to involve formation of the glycol perchlorate esters (after scission of ethers) which are explosive, those of ethylene glycol... 

So, at the beginning of the 25-year period here commemorated, alcohols, glycols, aldehydes, and ketones, chlorinated hydrocarbons, esters, and ethers—all so vital in their direct uses or as chemical building blocks—were beginning to be produced by synthesis from hydrocarbons provided by the already well-grown petroleum and natural gas industries. Subsequent developments came in rapid succession, with remarkably little in-... 

Cimbura and Kofoed (50),mentioned earlier, used GLC to separate amphetamine and methamphetamine after acetylation with acetic anhydride in methanol. Derivatives were extracted using diethyl ether and chromatographed op columns of either 3% OV-17, OV-1, or SE-30. Column temperature was 160°C. They also reported the chromatographic determination of acetylated morphine on 3% SE-30, OV-1, or OV-17 at temperatures of 220°C. Cruickshank et al.(21) separated 21 amino acids as their trifluoroacetylated methyl esters. The column was 5% neopentyl glycol succinate on Gas Chrom P. Column temperatures were both isothermal and programmed 65°C for 20 min at 1.5°C/min then 2°C/min until 42.5 min then 4°C/min until 60 min then isothermal until about 75 min (see Figure 12.2). Chang et al. (19), used BSA/pyridine to form the TMS derivatives of levodopa, methyldopa, tyrosine. 

---