A series of poly[2-(diisopropylamino)ethyl methacrylate]-block-poly[2-(N-morpholino)ethyl methacrylate], IPDPA-b-PMEMA], have been synthesized by using group transfer polymerization. These novel PDPA-b-PMEMA diblock copolymers dissolved molecularly in aqueous solution at low pH (<6.0) due to the protonation of all tertiary amine residues of both blocks and formed PDPA-core micelles at pH 7.5 by PMEMA block forming the micelle coronas. On the other hand, it was also observed that these diblock copolymers formed near-monodisperse 'reverse micelles', PMEMA-core micelles, in n-alkanes with or without requiring cosolvent depending on comonomer ratios. Dynamic light scattering studies indicated monodisperse or near-monodisperse micelles in both cases. The intensity-average radii of the PDPA-core and the PMEMA-core micelles were between 10 nm and 17 nm (polydispersity index, mu(2)/Gamma(2) < 0.08) and between 10 nm and 13 nm in n-hexane (mu(2)/Gamma(2) < 0.09), respectively. (C) 2008 Elsevier Ltd. All rights reserved.