Alkyl Polyglycosides derivatives

Nowadays,alkyl polyglycosides are available in sufficient quantities and at competitive costs so that their use as a raw material for the development of new speciality surfactants based on alkyl polyglycosides is arousing considerable interest. Thus, the surfactants properties of alkyl polyglycosides, for example foam and wetting, could be modified as required by chemical transformation.

Derivation of alkyl glycosides is a widely engaged work at present.There are many kinds of alkyl glycoside derivatives by means of nucleophilic substitution.In addition to reacting with esters or ethoxides, ionic alkyl polyglycoside derivatives, such as sulfates and phosphates, can also be synthesized.

Starting from alkyl polyglycosides having alkyl chains(R) of 8,10,12,14 and 16 carbon atoms（C₈ to C₁₆）and an average degree of polymerization(DP) of 1.1 to 1.5,three series of alkyl polyglycoside derivatives were prepared. In order to investigate the change in the surfactant properties hydrophilic or hydrophobic substituents were introduced leading to alkyl polyglycoside glycerol ethers. (Figure 1)

In view of their numerous hydroxyl groups, alkyl polyglycosides are over-functionalized molecules.by far the most alkyl polyglycoside derivatizations are carried out by chemical transformation of the free primary hydroxyl group at the C⁶ atom. Although primary hydroxyl groups are more reactive than secondary hydroxyl groups, this difference is not sufficient in most cases to achieve a selective reaction without protective groups.Accordingly, derivatization of an alkyl polyglycoside can always be expected to produce a product mixture of which the characterization involves considerable analytical effort. A combination of gas chromatography and mass spectrometry was shown to be the preferred analysis method. In the synthesis of alkyl polyglycoside derivatives, it has proved effective to use an alkyl polyglycoside with a low DP value of 1.1,in the following referred to as alkyl monoglycosides. This leads to less complex product mixtures and as a consequence to less complicated analyses.