Preparation and Properties of New Lactose-Based Suractans

摘要

A new group of non ionic saccharide-based sur- factants, N-alkanoyl-N-methyllactitolamines (alkanoyl: de- canoyl, lauroyl, myristoyl, palmitoyl, stearoyl), were synthe- sized and characterized. Surface properties such as critical mi- celle concentration, standard free energy of adsorption, standard free energy of micellization, surface tension reduc- tion efficiency, effectiveness of surface tension reduction, sur- face excess concentration, and surface area demand per mol- ecule as well as foaming properties (i.e., foam volume and foam stability), contact angle, antimicrobial activity, and biodegradability were determined. The selected performance properties were evaluated in relation to commercially avail- able alkyl polyglucosides (Glukopon 600 EC(HH)-a Henkel product), and oligooxyethylenated decyl (C10E4) and dodecyl (C12Es) alcohols. The foaming-stabilizing effect and contact angle suggest that the lactose-derived surfactants that were studied share some common properties with alkyl polygluco- sides that are different from those with an oligooxyethylene grouping. All tested N-alkanoyl-N-methyllactitolamines were practical,y nontoxic to bacteria and yeasts. These compounds are readily biodegradable in the Closed Bottle test inoculated with activated sludge. N-AlkanoyJ-N-methyJJactitoJamines with lower chain lengths (C1O-C14) biodegraded at a slightly faster rate. Biological properties showed that this class of com- pounds fulfills all requirements needed for environmental acceptance.