Acid ethoxylates ethoxy distribution

C 3-C,8 alkyl 3- to 11-mole ethoxylates ethoxy distribution Silica Gel 60 or Silica Gel 60 F-254, 0.25 mm 2-Butanone or 90 10 EtOH/HOAc or 80 20 BuOH/EtOH or 60 10 20 0.5 BuOH/EtOH/H20/ HOAc Acid Blue 158 49... 

Fatty acid amide 10-mole ethoxylate ethoxy distribution Merck Silica Gel 60 F-254, 0.25 mm, activated at 120- C for 15 min 80 14 10 ethyl acetate/HOAc/H20 or 95 5 acetone/HOAc Eosin modified Dragendorff reagent barium chloride/triiodide solution 9... 

Fatty acid 8-mole ethoxylates ethoxy distribution Merck Silica Gel G, activated at 120 Cfor30min 2-Butanone, saturated with water Modified Dragendorff reagent 41... 

TLC is suitable for showing the ethoxy distribution of an ethoxylated glycerol trioleate, as well as allowing estimation of free oleic acid (64,65). 

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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