title: Self-assembly and influence of the organic counterion in the ternary systems dodecylamine/acrylic acid/water and dodecylamine/methacrylic acid/water.
abstract: Due to complete proton transfer from the acid to the amine, a reaction between an equimolar mixture of dodecylamine and (meth)acrylic acid leads to the formation of dodecylammonium (meth)acrylate. The latter can be considered as a surfactant with a polymerizable organic counterion. The ternary phase diagrams of the two systems dodecylamine/acrylic acid/water and dodecylamine/methacrylic acid/water are described. Both systems can form isotropic solutions and lyotropic liquid crystalline lamellar phases. Moreover, the system with the methacrylate counterion can also form a cubic phase in the water-rich part of the phase diagram. The difference in the self-organization observed for the two systems is explained by the greater bulkiness and hydrophobicity of the methacrylate. Whereas the acrylate counterion behaves rather like a classic inorganic counterion, the methacrylate counterion resides in the outermost part of the aggregates, giving rise to a change in the surface curvature.
authors.affiliation: UNESCO Associated Centre for Macromolecules, Department of Chemistry and Polymer Science, University of Stellenbosch, Private Bag X1, 7602 Matieland, South Africa.
authors.forename: Patrice C
authors.initials: PC
authors.lastname: Hartmann
authors.forename: Philippe
authors.initials: P
authors.lastname: Dieudonné
authors.forename: Ronald D
authors.initials: RD
authors.lastname: Sanderson