Scaling relation of Complex Coacervate Core Micelles

Complex coacervation is a liquid-liquid phase separation when two oppositely charged polyelectrolytes are mixed in an aqueous solution. Because of the nature of electrostatic interaction, the coacervates are highly responsive to solution condition such as ionic strength. In this study, complex coacervate core micelles (C3Ms) are prepared by simple mixing of AB and A’B diblock copolyelectrolyte solutions in an aqueous solution where A and A’ are oppositely charged blocks, and B is PEO block. Owing to the coacervate cores, C3Ms have been used for stimuli-responsive vehicles in the field of food, cosmetics and biomedical industry. For wider utilization of C3Ms, understanding the scaling relation is significant. We have developed the scaling relation for C3Ms such as core dimension as a function of charged block length and ionic strength, and compared to experimental data obtained by light, x-ray, and neutron scattering measurements. These results are discussed in terms of current understanding of complex coacervates including free energy and interfacial tension.