Salt-induced swelling-to-shrinking transition in polyelectrolyte multilayer capsules.
We study the size of polyelectrolyte multilayer capsules as a function of ionic strength, temperature, and time. A dynamic micromechanical model is developed which successfully describes the experiments. The model includes the polymer-solvent surface tension, an electrostatic force which is strongly ionic strength dependent, and a temperature-dependent mobility parameter. The activation of >50 kT suggests that multiple ion pairs must be broken simultaneously in the process of chain rearrangement. In support of our physical model capsules can repeatedly swell and shrink by varying ionic strength.
Köhler
Karen
K
Max Planck Institute of Colloids and Interfaces, Wissenschaftspark Golm, 14424 Potsdam, Germany.
Biesheuvel
P Maarten
PM
Weinkamer
Richard
R
Möhwald
Helmuth
H
Sukhorukov
Gleb B
GB