title: Effect of ion pair formation on the structure of polymer micelles with ionic amphiphilic coronae.
abstract: We report a theoretical study of micelles from diblock copolymers with an insoluble core-forming block and an amphiphilic ionic corona-forming block. We calculate the micelle structural parameters depending on the composition of the coronal block (ratio between the non-polar and ion-containing groups) as well as solvent quality and polarity for the coronal block. We focus on the effect of ion pair formation in a low polar corona medium and predict the existence of novel micelles with ionomer-type coronae. In these micelles most part of counterions is bound with ions in polymer chains. Two consecutive jump-like first-order phase transitions between different-type micelles can take place in the solution upon change of hydrophobic/polyelectrolyte balance within the micelle corona: large micelles with polyelectrolyte collapsed coronae → large micelles with ionomer-type coronae → small micelles with polyelectrolyte swollen coronae. These transitions are accompanied by non-monotonous change in the micelle aggregation number. New insight into the role of counterions is important for design of stimuli responsive systems.
authors.affiliation: Physics Department, Moscow State University, Moscow 119991, Russia.
authors.forename: A M
authors.initials: AM
authors.lastname: Rumyantsev
authors.forename: E Yu
authors.initials: EY
authors.lastname: Kramarenko
mesh_terms: D057927:Hydrophobic and Hydrophilic Interactions; D007477:Ions / Q000737:chemistry; D008823:Micelles; D015394:Molecular Structure; D011108:Polymers / Q000737:chemistry*; D013501:Surface-Active Agents / Q000737:chemistry*
chemical_list: D007477:Ions; D008823:Micelles; D011108:Polymers; D013501:Surface-Active Agents