Multicomponent Self-Assembly and Self-Sorting of Polymer Micelles in Water: Selective and Switchable Association by Kinetic or Thermodynamic Control

Herein, we report multicomponent self-assembly and self-sorting of polymer micelles in water using mixtures of an anionic random copolymer bearing sodium sulfonate and dodecyl groups and random copolymers carrying poly(ethylene glycol) (PEG) and alkyl groups. In pure water, the anionic copolymer is co-self-assembled with the PEG copolymers to form anion/PEG-fused micelles with a controlled aggregation number. By designing the composition or alkyl groups of PEG copolymers, the fused micelle is reversibly self-sorted into discrete anion or PEG micelles in the presence of NaCl. Co-self-assembly of the anionic copolymer and PEG copolymers is kinetically or thermodynamically controlled, depending on the dynamic properties of the PEG copolymer micelles. Thus, the selective self-assembly of ternary copolymers is also controllable and switchable by temperature: A kinetically favored anion/PEG-fused micelle is predominantly formed in the presence of a kinetically frozen PEG micelle at low temperature, whereas the fused micelle is transformed via polymer chain exchange upon heating into a thermodynamically more stable anion/PEG-fused micelle.