Diversity of nanostructured self-assemblies from a pH-responsive ABC terpolymer in aqueous media

We report on the diverse self-assembly of the poly(2-vinyl pyridine)-b-poly(acrylic acid)-b-poly(n-butyl methacrylate) (P2VP-PAA-PnBMA) ABC terpolymer in aqueous solutions. This has allowed us to fabricate a range of hierarchically organized nanostructured particles and hydrogels just by tuning both the pH and the concentration of polymer solutions. The multiresponsive molecule demonstrates a unique diversity of structural organizations caused by the combination of the P2VP and PAA building blocks. We found conditions for the formation of thermosensitive centrosymmetric core- shell -corona micelles, compact spheres, polyelectrolyte flowerlike micelles, a charged pH-sensitive 3D network, toroidal nanostructures, and finite size clusters (microgels). The transition between different micelles and the hydrogel was induced via the regulation of electrostatic and hydrophobic interactions in the system.