Novel Ethoxylated Inositol Derivatives - Chemical Mixtures of Sugar- and Oligo(ethylene oxide)-based Surfactants

Sugarand oligo(ethylene oxide)-based surfactants behave quite differently despite of both being non-ionic surfactants. In a large number of studies the properties and behaviour of these two different kinds of surfactants were addressed. However, it was only recently that an extensive investigation has been carried out on the properties of respective mixtures focussing on mixtures of β-C12G2 (n-dodecyl-β-D-maltoside) and C12E6 (hexaoxyethylene dodecyl ether) [1, and references therein]. A question arises: how “chemical” mixture of these surfactants would behave. Such chemical mixtures would be surfactants the head group of which contains chemically connected sugar and oligo(ethylene oxide) units. In order to study the behaviour of this sort of compounds we synthesized a new class of surfactants whose head group consists of one sugar unit and three ethylene oxide units. As surrogate for sugar we employed a somewhat exotic but nevertheless readily available family of carbohydrate-like compounds called inositols (cyclohexane-1,2,3,4,5,6-hexols) of which we used myo-inositol for the synthesis of new surfactants [2-4]. Inositols are renewable, nontoxic starting materials which compared to traditional pyranosidic or furanosidic sugar derivatives present the advantage of a high thermal and chemical stability. We synthesized new regiochemically defined ethoxylated inositol derivatives and studied their thermotropic and lyotropic liquid crystalline properties as well as their surface activities. The results will be presented, compared with those obtained for surfactants with similar structures, and discussed in terms of structure-property relations.