Aliphatic glycols

The dichlorides of aliphatic glycols are obtained by reaction with thionyl chloride in the presence of a small quantity of pyridine, for example ... 

The dibrotnides of aliphatic glycols are best prepared by mixing the glycol with a cold hydrobromic acid - sulphuric acid mixture, allowing to stand for 24 hours, and heating on a steam bath for three hours ... 

Recently, in extending the reaction to aliphatic glycols, Ghera observed that p-nitrobenzoate esters gave better results than acetates, and that zinc acetate could be substituted for activated zinc. He has proposed that the rearrangement is a heterogeneous catalytic process, with the zinc acting as a Lewis acid ... 

Habid and Malek49 who studied the activity of metal derivatives in the catalyzed esterification of aromatic carboxylic acids with aliphatic glycols found a reaction order of 0.5 relative to the catalyst for Ti(OBu)4, tin(II) oxalate and lead(II) oxide. As we have already mentioned in connection with other examples, it appears that the activation enthalpies of the esterifications carried out in the presence of Ti, Sn and Pb derivatives are very close to those reported by Hartman et al.207,208 for the acid-catalyzed esterification of benzoic and substituted benzoic acids with cyclohexanol. These enthalpies also approach those reported by Matsuzaki and Mitani268 for the esterification of benzoic acids with 1,2-ethanediol in the absence of a catalyst. On the other hand, when activation entropies are considered, a difference exists between the esterification of benzoic acid with 1,2-ethanediol catalyzed by Ti, Sn and Pb derivatives and the non-catalyzed reaction268. Thus, activation enthalpies are nearly the same for metal ion-catalyzed and non-catalyzed reactions whereas the activation entropy of the metal ion-catalyzed reaction is much lower than that of the non-catalyzed reaction. 

Jackson, Jr, W. J. and Morris, J. C., Poly esters of 4,4 -biphenyl dicarboxylic acid and aliphatic glycols for high-performance plastics, in Liquid Crystalline Polymers, ACS Symposium Series, Vol. 453, American Chemical Society, Washington, DC, 1990, pp. 16-32. 

An aliphatic glycol monoether cosolvent (e.g., dipropylene glycol monomethyl ether)... 

Specialty Epoxy Resins. In addition to bisphenol, other polyols such as aliphatic glycols and novolaks are used to produce specialty resins. Epoxy resins may also include compounds based on aliphatic, cycloaliphatic, aromatic, and heterocyclic backbones. Glycidylation of active hydrogen-containing structures with epichlorohydrin and epoxidation of olefins with peracetic acid remain the important commercial procedures for introducing the oxirane group into various precursors of epoxy resins. 

Although no mechanism is proposed for the dimerization of lactic acid in the FSOsH-SbFs solution, the process may very well involve the superelectrophile 147. Other oxonium-carbenium 1,3-dications have been suggested in superacid promoted pinacolone rearrangments of diprotonated aliphatic glycols and alkoxy alcohols (eqs 49-50).58... 

In this paper, we have evaluated three different protocols for the preparation of AQ-enzyme film using choline and glucose oxidases and mixture of AQ 29D and AQ 55D (1 1). This AQ mixture is recommended by Eastman Kodak to increase the adherency of the film to a surface such as a platinum electrode (17). The values 29 and 55 represent the glass transition temperature of each polymer. Also, the main structural difference between the two polymers is that, in the case of AQ 55D, an aliphatic glycol moiety replaces the cycloaliphatic glycol moiety found in the AQ29 (17,18). 

Polyesters of 4,4 -Biphenyldicarboxylic Acid and Aliphatic Glycols for High-Performance... 

Thermotropic liquid crystalline polyesters (ICP s) were prepared from the dimethyl ester of 4,4 -bi-pheriyldicarboxylic acid (BDA) and aliphatic glycols containing 2 to 10 methylene units and ccnpared with similar trans-4,41 -stilbenedicarboxyl ic acid (SDA)... 

Aliphatic-aromatic liquid-crystalline polymers, synthesis, 16-17 Aliphatic glycol polyesters experimental procedures, 17-18 properties, 17... 

Prior to 1978, the work in this area mainly dealt with the synthesis of tri-, tetra-, and pentavalent metal and metalloid derivatives of aliphatic (glycol) and aromatic (catechol/substituted catechol) diols (6, 423), of a wide variety of structural types. These types depended on (a) the nature of the metal and metalloid and their oxidation states, (b) the type of diol, and (c) the reactants stoichiometries. Out of a large number of structural possibilities, the common types reported earlier are shown in Fig. 65, without X-ray crystallographic authentication. 

Unsaturated polyesters obtained by polycondensation of saturated and unsaturated acids, anhydrides and aliphatic glycols are used as coating resins and as matrices in glass-reiforced products. 

Detoxicated by hydrolysis to the corresponding aldehyde and aliphatic glycol, which both are completely metabolized by known pathways. 

Features Provides superior exterior durability Properties Amber clear liq. sol. in aromatics, aliphatics, glycol ethers limited sol. in esters, alcohols insol. in water, ketones dens. 10 Ib/gal 25% act. 

Classification Aliphatic ether alcohol aliphatic glycol ether... 

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