Acid ethoxylates description

Tween 20, Chemical Classification - Ethoxylated Fatty Acids, Chemical Description -Polyoxyethylene (20) Sorbitan Monolaurate, Hydrophile-Lipophile Balance (HLB) 16.7, Uniqema, 1000 Uniqema Blvd., New Castle, Delaware 19720. 

Description. This class of surfactants is a subcategory of the above surfactant group based on carboxylic acids they are monoesters of di- and tricarboxylic acids. These esters are produced by condensation reactions involving different types of molecule either an alcohol with a polycarboxylic acid (e.g., tartric or citric acid), or an hydroxyacid (e.g., lactic acid) with a carboxylic acid. The reacting alcohol may have been previously ethoxylated. 

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. 

Description. Esterified quaternaries (or esterquats) are produced by the esterification of the hydroxyl group(s) of secondary or tertiary amino alcohols (e.g., diethanol amine, imidazoline derivative, etc.) with selected fatty acids. The above starting amino alcohols can result from the ethoxylation of straight amines. The resulting esteramine is further quatemized by adequate quatemizing agents (e.g., dimethylsulfate, methylchloride, etc.). 

Description. This class of surfactants essentially covers ethoxylated derivatives of lanolin (wool fat) and castor oil. Lanolin is the generic name of a wax containing a complex mixture of esters and polyesters of high-molecular-weight alcohols (aliphatic, steroid, and triterpenoid) and fatty acids (saturated, unsaturated, hydroxylated, and non-hydroxylated). The ethoxylation is carried out on fractionation products of lanolin (lower aliphatic alcohols and sterols). 

Description. Surfactants of this class are better known as sugar esters or sucrose esters. The sucrose esters are obtained by transesterification of sucrose with fatty acid methyl esters or triglycerides, leaving methanol or glycerol as by-products, respectively- Mono- and diesters are the major products. Due to the steric effects,-primary hydroxyl groups are almost exclusively subject to esterification. Both types of esters exhibit the general properties of common nonionics (i.e., ethoxylated alcohols). 

Anyone seeking to characterize ethoxylated acids should study the specifications and descriptions of the fatty acid starting materials, for which excellent brochures are available from major suppliers. For example, the oleic acid of commerce is a mixture of carboxyhc acids but also contains other materials, which can total several percent. The purchaser has a choice of several grades of this so-called oleic acid, with the pharmaceutical grades not necessarily being the purest. Consider the fate of the impurities during the ethoxylation reaction to predict what might be likely impurities in the final product. 

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