Zum Eigenschaftsbild der Alkylpolyglucoside

Abstract

Besides the old soap the alkyl polyglucosides meanwhile have become the most important surfactants based on natural raw materials. They are highly interfacial active. This is true to liquid/gas, liquid/liquid and liquid/solid interfaces. They form weakly negative charged, highly anisometrical micelles with high aggregation numbers. The phase behaviour of alkyl polyglucosides with alkyl chain lengths exceeding C 11 and with not too high degrees of glucosidation is determined by distinct regions of coacervation as is the case with ethoxylates. Similarly they have a cloud point but it depends much more on the chemical structure than that of the ethoxylates. The cloud point is therefore well suited for quick product control. The strong effect of the structure on the coacervation as well as the dense package of the alkyl polyglucosides in the interface films and the high aggregation numbers indicate an extremely strong molecular interaction which is obviously typical for surfactants with cumulated OH-groups. The wormlike micelles which are supposed to be formed in higher alkyl polyglucoside concentrations have a strong effect on the rheological properties of aqueous surfactant solutions. This applies to the viscosity and to a greater extent to the elasticity.