Chain flexibility effect on complex coacervate core micelles

Complex coacervate core micelles (C3Ms) have been investigated in a wide range of applications owing to stimuli-responsiveness and hydrophilic cores. Assembly of two oppositely charged block copolyelectrolytes leads to the formation of C3Ms based on the chain length recognition. Therefore, it was limited to form various structures by mixing block copolyelectrolytes having different lengths. In this study, we investigated the structure of C3Ms formed by mixing of block copolyelectrolytes having different lengths characterized by dynamic light scattering (DLS) and small angle X-ray scattering (SAXS) measurements. A well-defined poly(ethylene oxide-b-allyl glycidyl ether) (PEO-PAGE) was synthesized and functionalized with charged moieties including ammonium (A) and sulfonate (S). The C3M is formed by mixing of oppositely charged block copolyelectrolyte solutions of different lengths due to the degree of conformational freedom of the ether backbone. The relatively shorter chains are stretched to the center of the C3Ms core, because of core-corona junction alignment at interface. The core dimensions are associated with the average number of charged block, and it is captured by free energy theory for block copolymer micelle systems.