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[...]... production conditions and to prepare the market for a new class ofsurfactants New peaks in the commercial exploitation of alkyl polyglycosides (APG) were reached in 1992 with the inauguration of a 25,000 t.p.a production plant for APG surfactants by Henkel Corporation in the United States and in 1995 with the opening of a second plant of equal capacity by Henkel KGaA in Germany [9] II TECHNOLOGY Any... mixtures of species which differ mainly in the degree of polymerization (a typical distribution is given in Table 1) and in the length of the alkyl chains Alkyl monoglycosides are the main group of components with a content of > 50%, followed by the diglycosides and higher oligomers up to heptaglycosides Small amounts of more highly glycosidated species are also present Species with a degree of glycosidation... Static surface tension of alkyl glycosides with different alkyl chain lengths as a function of the concentration in distilled water at 60°C 16 Schmid and Tesmann FIG 12 Static surface tension of C12/14-APG and C12/14 FAS and 1:1 and 4:1 mixtures thereof as a function of the concentration in distilled water at 60°C (From Ref 17.) surfactants, as measured at 60°C [40] The values of the mixtures are close... capacity of FAS and FAES (c) Dermatological Behavior Manual dishwashing detergents belong to the category of products which very frequently come into contact with the skin of the consumer, albeit in dilute form Accordingly, the skin compatibility of this group of products is of particular interest Alkyl polyglycosides are not only mild on the skin, but can significantly reduce the skin irritation of anionic... contents III PHYSICOCHEMICAL PROPERTIES OF ALKYL POLYGLYCOSIDES A Surface Tension The surface tension of alkyl (poly)glycosides was investigated as a function of the alkyl chain and the degree of polymerization (DP) using samples differing in composition In addition to pure surfactants for characterizing the basic depen- 14 FIG 9 FIG 10 Schmid and Tesmann HTGC chromatogram of long-chain alkyl polyglycoside... by comparison with the number of glucoside groups of the alkyl polyglycosides The surface tension behavior of mixtures of alkyl polyglycosides and anionic surfactants was investigated with reference to an alkyl polyglycoside/fattyalcohol sulfate (FAS) mixture Figure 12 shows the surface tension/concentration curves at 60°C for C12/14-APG, C12/14-FAS, and two mixtures of these TABLE 2 cmc Values from... product side If a relatively large amount of water is produced per unit of time, for example by high reaction temperatures, provision has to be made for the effective removal of this water from the reaction mixture This minimizes secondary reactions (particularly the formation of polydextrose) which take place in the presence of water The evaporation efficiency of a reaction stage depends not only on... observed behavior of mixtures of anionic and nonionic surfactants differing considerably in their CMC values [41] B Phase Behavior The nonionic class of alkyl polyglycosides differs from fatty-alcohol ethoxylates by its characteristic structure which considerably affects the association of molecules in solution, the phase behavior, and the interfacial activity The hydrophilic head of the glucose ring,... Behavior A feature of many conventional nonionic surfactants, such as FAEO, is their relatively low foaming capacity, alone or in combination with conventional anionic surfactants In contrast, alkyl polyglycosides, which, when combined with anionic surfactants, show favorable foaming behavior, i.e increase the foam volume or keep it at a high level Figure 20 shows by way of example the influence of C12/14-APG... used and by the chain length of the alcohol used as described here for the production of alkyl polyglycosides on the basis of octanol/decanol and dodecanol/tetradecanol Under the conditions of the acid-catalyzed syntheses of alkyl polyglycosides, secondary products, such as polydextrose [26,27], ethers, and colored impurities, 8 FIG 5 Schmid and Tesmann Alkyl polyglycoside surfactants industrial synthesis . well with different types of dirt and stains
under a variety of water conditions.
In recent years, however, a number of specialty surfactants have been developed
for. Nitrogen-Containing Specialty Surfactants 71
Shoaib Arif and Floyd E. Friedli
3. Sulfonated Methyl Esters 117
Terri Germain
4. Detergency Properties of Alkyldiphenyl