Alcohol ethoxylates ethoxy distribution

Various fatty alcohol 8-mole ethoxylates ethoxy distribution Merck Silica Gel G, activated at 120 C for 30 min 2-Butanone, saturated with H2O Modified Dragendorff reagent 43... 

Ethoxylated or propoxylated fatty alcohol acrylate or methacrylate compoimds are useful as defoamers for concrete compositions (28). It has been observed that a special balance between the chain length of the fatty alcohol and the distribution of the ethoxy or propoxy units results in an ester with improved defoaming properties. These products are particularly efficient in removing occluded air bubbles and foams formed during concrete processing operations. This is unusual, since the structures miss polymeric backbones. 

Sulfated C12-C15 alcohol 3-mole ethoxylate homolog distribution separation by both alkyl and ethoxy chain length... 

Sulfated C12-C15 alcohol 3-mole ethoxylate homolog distribution separation by both alkyl and ethoxy chain length Sulfated C12-C15 alcohol 3-mole ethoxylate determination of alkyl chain length distribution Sulfated C12-C14 alcohol ethoxylate determination of alkyl chain length distribution Sulfated C10-C14 alcohol ethoxylate determination of alkyl chain length distribution separation of isomers... 

Cg, C9, and C12 APE, E = 1 to 48 ethoxy distribution higher Rf with higher ethoxylation Whatman chromatography paper grade 1 impregnated with cetyl alcohol 70 20 10 H20/EtOH/HCl Draggendorff reagent 136... 

Elhoxylated alcohol distributions from 2 to 40 ethylene oxide units (e.g., Brij 76) were characterized on a diol phase (ELSD) using a 25-min 90/10->20/80 hexane/(98/2 chloroform/IPA) gradient [645]. Good separation throughout the homologous series resulted. Peak shapes were acceptable as well. Tables of retention times for hexadecylalcohol-ethoxylated compounds (1-6 ethoxy groups) and for Cio-Cig hexaethoxylated alcohols were presented. 

Description. Alkyl ether sulfates (AES), which are also called alcohol ethoxy sulfates (AEOS), result from the sulfation of an ethoxylated alcohol. As will be mentioned in a later section covering the ethoxylated alcohols, there is usually, and more especially in industrial-grade raw materials, a rather broad distribution in the ethoxylation degree. The ether sulfates are stable under alkaline conditions but are rapidly hydrolyzed under acidic conditions and even under neutral conditions this hydrolysis is ascribed to an autocatalytic acidification process that progressively takes place and continues growing. 

The determination of alkyl chain distribution of alcohol ether sulfates can be most easily performed by gas chromatography after cleavage of the sulfated ethoxy moiety with hydri-odic acid. This procedure is similar to that described under the analysis of ethoxylated nonionic surfactants. The alkyl iodides from cleavage may also be determined by HPLC (72). An alternative approach requires the decomposition of the sulfate and ethoxy groups with the mixed anhydrides of paratoluenesulfonic and acetic acid, followed by GC determination of the alcohol acetates (73). 

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