Surfactants from glucamines and omega-epoxy fatty acid esters

The ring-opening reaction of omega -epoxy fatty acid methyl esters (9,10-ep oxy decanoic acid methyl ester, 10,11-epoxy undecanoic acid methyl ester an d 13,14-epoxy tetradecanoic acid methyl ester) with N-methyl glucamine or g lucamine was studied. A new method (in methanol under reflux) leads to prod ucts, which are surfactants of linear or Y-type-structure, in fair yields a nd purities. In a following step the ring-opening products were saponificat ed by enzymatic catalysis or by conversion with sodium hydroxide leading to amphoteric surfactants. The surface-active properties of the methyl esters and their corresponding acids or salts were studied at various pH-values b y measurement of surface tension of aqueous solutions and by examination of foaming properties. Depending on the chain length of the used epoxides, th e structure of the obtained sugar-based surfactant and the pH-values, diffe rent surface-active properties were observed. Several of the achieved produ cts reduce the surface tension of aqueous solution down to 26-40 mN/m. Exam ination of foaming properties of the latter show rather poor or good foamer s, depending on the surfactant used or the pH-value of the solution.