Core and Corona Structure of Mixed Polymeric Micelles

Mixed polymeric micelles have been prepared from aqueous solutions of poly(2-(dimethylamino)ethyl methacrylate)-<i>block</i>-poly(glyceryl methacrylate), PDMAEMA<sub>45</sub>-<i>b</i>-PGMA<sub>90</sub>, and poly(acrylic acid)-<i>block</i>-poly(acrylamide), PAA<sub>42</sub>-<i>b</i>-PAAm<sub>417</sub>, through complex coacervation of the oppositely charged blocks. Rather monodisperse, spherical aggregates are formed with a <i>R</i><sub>h</sub> = 15.2 ± 0.4 nm. The extent of chain mixing between poly(acrylic acid) and poly(2-(dimethylamino)ethyl methacrylate) in the micellar core and poly(acrylamide) and poly(glyceryl methacrylate) in the micellar corona has been investigated by 2D <sup>1</sup>H NMR NOESY experiments. The presence of cross-peaks for protons in different core and corona blocks indicates that the two blocks are in close proximity (<0.5 nm) and micelles are formed in which both core and corona are mixed.