Alkyl polyglycosides derivatives

The most extensive group of ether surfactants is that of polyethoxylated long-chain alcohols and related ethoxylated products considered, in view of their practical importance, in a separate section. Other ether nonionics of importance are polypropylene glycols, propoxylated alcohols, block-copolymers of ethylene oxide and propylene oxide, block-copolymers of ethylene oxide and butylene oxide [8, 16-20], block-copolymers having a hydrophobic polydimethylsiloxane moiety [19, 21], as well as alkyl polyglycerides, alkyl polyglycosides, derivatives of maltose and other saccarides. 

The derivatization of alkyl polyglycosides is currently being pursued with great commitment [15,24,119,120]. A broad range of alkyl polyglycoside derivatives can be obtained by using relatively simple methods, such as nucleophilic substitution. Besides the reaction to esters or ethoxylates, ionic alkyl polyglycoside derivatives, such as sulfates and phosphates, can also be synthesized (Fig. 41). 

The interfacial tension measurements were carried out with a Kruss spinning drop tensiometer. To simulate practical conditions, the measurements were performed in hard water (270 ppm Ca Mg = 5 1) at a surfactant concentration of 0.15 g/L and at 50 °C. Figure 46 shows a comparison of the interfacial tension of C12 alkyl polyglycoside derivatives against octyl dodecanol. The C12 monobutyl ether has the highest interfacial tension and hence... 

Anionic alkyl polyglycoside derivatives Cognis, Cesalpina Personal care ... 

The glycosidation of the reducing sugars obtained from hemicelluloses leads to the alkyl polypentosides surfactants. Glycosylation needs fatty alcohols as raw materials. Natural fatty alcohols derived, for example, from coconut or palm kernel oil are used in the alkyl polyglycoside synthesis to buUd up the hydrophobic part of the surfactants. These alcohols are used as blends obtained after transesterification and fractionation of oils leading to corresponding fatty acid methyl esters, and... 

Henkel makes alkyl polyglycoside surfactants from alcohols derived from coconut and palm oils, and glucose derived from cornstarch.277 The preparation can be done with /3-D-glucosidase.278 Sucrose monoesters of long-chain fatty acids can also be made enzymatically.279 A variety of biosurfactants are produced by various organisms that can be grown in culture.280... 

The hydrophilic part of the alkyl polyglycoside molecule is derived from a carbohydrate. Based on starch from corn, wheat, or potatoes, both polymeric and monomeric carbohydrates are suitable as raw materials for the production of alkyl polyglycosides. Polymeric carbohydrates include, for example, starch or glucose syrups with low degradation levels, whereas monomeric carbohydrates can be any of the various forms in which glucose is available,... 

The first step is to preconcentrate and separate the material of interest from the matrix by solid-phase extraction. The solid-phase material used is hydro-phobic silica gel (octadecyltrichlorosilane derivative). After preconditioning with methanol, 0.1-1 L of sample solution is passed through the cartridge or empore disk. After rinsing with water, the adsorbed surfactant is eluted with methanol. Recovery is in the 95-100% range. In the extract, alkyl polyglycosides are determined by HPLC or GC methods identical to or comparable with those already described. 

The influence of surfactants on the barrier function of the epidermis either by deterioration of the functional structure or by elution of components (homy layer lipids, NMF) is characterized by evaporimeter measurements as a change of the natural transepidermal water loss (TEWL). Investigations in connection with the arm flex wash test show that the changes in relation to the normal state of the skin barrier produced by standard surfactants are reduced in the presence of alkyl polyglycosides. This effect can be increased in the systematic buildup of formulations by incorporating further additives, such as protein derivatives [70,75]. 

Rhode, O., Weuthen, M. and Nickel, D. (1997) New nonionic derivatives of alkyl polyglycosides - synthesis and properties, in Alkyl Polyglycosides - Technology, Properties and Applications, Chapter 8, Wiley-VCH Verlag GmbH, Weinheim, pp. 139-149. 

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