Ethylene glycol reaction

Fig. 6. Effect of temperature on rhodium-catalyzed CO hydrogenation ( ) methanol ( ) ethylene glycol. Reaction conditions 75 ml y-butyrolactone solvent, 3 mmol Rh, 10.5 mmol 2-hydroxypyridine, 0.5 mmol cesium 2-pyridinolate, 544 atm, H2/CO = 1, 4 hr (88).

Course of the reaction. In Table I, data are presented from two typical experiments which show the relative rates of formation of ammonia and carbon dioxide. These data serve to indicate a possible course of the urea-ethylene glycol reaction. Clearly, the synthesis of ethyleneurea did not proceed through simple elimination of two moles of water from an equimolar mixture of reactants for there was no evidence that water per se was obtained from the reaction. Indeed, it did not appear to be even a primary product since, if it had been and if it had reacted with urea, then the quantity of carbon dioxide relative to ammonia would have been much higher in the early stages of the reaction. From the very large quantity of ammonia evolved it appeared that the primary product was a carbamate. This carbamic acid ester of ethylene glycol subsequently lost carbon dioxide with formation of the desired C—N bond as indicated by the following equations ... 

Elimination of a water molecule takes place with various types of radicals and is catalysed by acids and bases. This has been observed with the radicals from ethylene glycol [reaction (64)] (von Sonntag and Thoms, 1970 Burchill and Perron, 1971) and other glycols, and... 

Figure 6. Esterification of terephthalic acid with ethylene glycol reaction temperature 473 K, reaction time 90 min.

On the other hand, thallic ion oxidizes olefins to a mixture of glycols and carbonyl compounds—e.g., ethylene gives acetaldehyde and ethylene glycol (Reaction 2). 

Poly(vinyl chloride) is a less useful polymer than poly(ethylene glycol). Reactions of Poly(mcthyl methacrylate)... 

PPG-1-PEG-9 lauryl glycol ether Synonyms POE (9) POP (1) lauryl glycol ether POP (1) POE (9) lauryl glycol ether Definition Ethoxylated, propoxylated ether of a lauryl epoxide and ethylene glycol reaction prod. Uses Emulsifier in cosmetics PPG-3-PEG-6 oleyl ether CAS 59112-62-8... 

Table 3.1 Kinetic rate constants of several uncatalyzed diisocyanate-poly(ethylene glycol) reactions at several temperatures. The initial molar ratio of diisocyanate to polyol is 2 1.

Scheme 6.112 Pathways to ethylene glycol (reactions framed by dashed line refers to discussion in this chapter).

CH2C1 CH2C1. Colourless liquid with an odour like that of chloroform b.p. 84 C. It is an excellent solvent for fats and waxes. Was first known as oil of Dutch chemists . Manufactured by the vapour- or liquid-phase reaction of ethene and chlorine in the presence of a catalyst. It reacts with anhydrous ethano-ales to give ethylene glycol diethanoate and with ammonia to give elhylenediamine, these reactions being employed for the manufacture of these chemicals. It burns only with difficulty and is not decomposed by boiling water. 

Condensation polymerization differs from addition polymerization in that the polymer is formed by reaction of monomers, each step in the process resulting in the elimination of some easily removed molecule (often water). E.g. the polyester polyethylene terephthalate (Terylene) is formed by the condensation polymerization (polycondensation) of ethylene glycol with terephthalic acid ... 

In this reaction the ethylene is oxidised to ethylene glycol, C H4(OH). ... 

Di-alkyl ethers of ethylene glycol, ROCHjCHjOR. The dimethyl ether, b.p. 85°/760 mm., is miscible with water, is a good solvent for organic compounds, and is an excellent inert reaction medium. The diethyl ether (diethyl cdloaolve), b.p. 121-57760 mm., is partially miscible with water (21 per cent, at 20°). 

Upon reaction with an alcohol in the presence of a catalyst, the monoalkyl ether of ethylene glycol is obtained ... 

Polymerisation of a diol with a dicarboxybe acid is exemplified by the production of a polyester from ethylene glycol and terephthabc acid either by direct esterification or by a catalysed ester-interchange reaction. The resulting polyester (Terylene) is used for the manufacture of fibres and fabrics, and has high tensile strength and resibency its structure is probably ... 

Diols that bear two hydroxyl groups m a 1 2 or 1 3 relationship to each other yield cyclic acetals on reaction with either aldehydes or ketones The five membered cyclic acetals derived from ethylene glycol (12 ethanediol) are the most commonly encoun tered examples Often the position of equilibrium is made more favorable by removing the water formed m the reaction by azeotropic distillation with benzene or toluene... 

Poly(ethylene Terephthalate). Poly(ethylene terephthalate) is prepared by the reaction of either terephthalic acid or dimethyl terephthalate with ethylene glycol, and its repeating unit has the general structure. 

Ester interchange reactions are valuable, since, say, methyl esters of di-carboxylic acids are often more soluble and easier to purify than the diacid itself. The methanol by-product is easily removed by evaporation. Poly (ethylene terephthalate) is an example of a polymer prepared by double application of reaction 4 in Table 5.3. The first stage of the reaction is conducted at temperatures below 200°C and involves the interchange of dimethyl terephthalate with ethylene glycol... 

The rate of this reaction is increased by using excess ethylene glycol, and removal of the methanol is assured by the elevated temperature. Polymer is produced in the second stage after the temperature is raised above the melting point of the polymer, about 260°C. 

The ethylene glycol liberated by reaction (5.L) is removed by lowering the pressure or purging with an inert gas. Because the ethylene glycol produced by reaction (5.L) is removed, proper stoichiometry is assured by proceeding via the intermediate, bis(2-hydroxyethyl) terephthalate otherwise the excess glycol used initially would have a deleterious effect on the degree of polymerization. Poly(ethylene terephthalate) is more familiar by some of its trade names Mylar as a film and Dacron, Kodel, or Terylene as fibers it is also known by the acronym PET. 

Reactions of the Methyl Groups. These reactions include oxidation, polycondensation, and ammoxidation. PX can be oxidized to both terephthahc acid and dimethyl terephthalate, which ate then condensed with ethylene glycol to form polyesters. Oxidation of OX yields phthaUc anhydride, which is used in the production of esters. These ate used as plasticizers for synthetic polymers. MX is oxidized to isophthaUc acid, which is also converted to esters and eventually used in plasticizers and resins (see Phthalic acids and otherbenzenepolycarboxylic acids). 

Reactions with Alcohols, Mercaptans, and Phenols. Alcohols add readily to acetaldehyde in the presence of trace quantities of mineral acid to form acetals eg, ethanol and acetaldehyde form diethyl acetal [105-57-7] (65). Similarly, cycHc acetals are formed by reactions with glycols and other polyhydroxy compounds eg, ethylene glycol [107-21-1] and acetaldehyde give 2-methyl-1,3-dioxolane [497-26-7] (66) ... 

Acryhc stmctural adhesives have been modified by elastomers in order to obtain a phase-separated, toughened system. A significant contribution in this technology has been made in which acryhc adhesives were modified by the addition of chlorosulfonated polyethylene to obtain a phase-separated stmctural adhesive (11). Such adhesives also contain methyl methacrylate, glacial methacrylic acid, and cross-linkers such as ethylene glycol dimethacrylate [97-90-5]. The polymerization initiation system, which includes cumene hydroperoxide, N,1S7-dimethyl- -toluidine, and saccharin, can be apphed to the adherend surface as a primer, or it can be formulated as the second part of a two-part adhesive. Modification of cyanoacrylates using elastomers has also been attempted copolymers of acrylonitrile, butadiene, and styrene ethylene copolymers with methylacrylate or copolymers of methacrylates with butadiene and styrene have been used. However, because of the extreme reactivity of the monomer, modification of cyanoacrylate adhesives is very difficult and material purity is essential in order to be able to modify the cyanoacrylate without causing premature reaction. 

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