Block-copolymer micelles with a interpolyelectrolyte crown

摘要

AbstractThe dispersion stability, structure, and properties of polymer micelles with the hydrophobic core and the interpolyelectrolyte crown in dilute water–salt solutions are studied by turbidimetry, velocity sedimentation, static and dynamic light scattering, fluorescence spectroscopy, and electron microscopy, as well as by measuring the electrophoretic mobility of the particles. The micelles are obtained by mixing diblock copolymers PS–block-poly(N-ethyl-4-vinylpyridine bromide) andPS–block-poly(acrylic acid) by a specially developed technique of water introduction in the mixture of copolymers in a nonselective organic solvent. It is found that the dispersion stability and the structural and physicochemical characteristics of micelles with the interpolyelectrolyte crown depend on the balance of electrostatic interactions of similarly and oppositely charged units in the crown. In turn, this balance is determined by the composition of the interpolyelectrolyte crown as well as by the pH and ionic strength of solution. It is shown that the micelles with the interpolyelectrolyte crown can be considered to be a special type of polyelectrolyte nanoparticles combining the properties of polyelectrolyte micelles and interpolyelectrolyte complexes. The unique ability of such micelles to electrostatically bind similarly charged polyions with a high linear charge density to the crown is demonstrated. It is first found that such a binding can be selective.]]>