THE SYNTHESIS AND SURFACE-ACTIVITY OF SOME ALKANEDIYL BISMORPHOLINES

This paper reports on the synthesis and surface activity of some 4,4'-(N,N'-alkanediyl)bismorpholine compounds. Surface tension measurements indicate that bismorpholines with hexane or nonane as the n-alkane group behave effectively as surfactants in aqueous solution. The dihydrochloride salt of nonanediyl bismorpholine also exhibits surface activity. Reductions in the surface tension of water to below 30 mN m(-1) are found in some instances. A discontinuity in surface tension observed for the nonanediyl bismorpholine compound is attributed to the onset of a phase transition and not micellisation. The cross-sectional area occupied by the bismorpholines is consistent with both morpholino head-groups being adsorbed at the solution-air interface. A substantially larger cross-sectional area per molecule found for the highly water-soluble dihydrochloride salt is attributed to partitioning into the bulk phase.