Core and Corona Structure of Mixed Polymeric Micelles

Mixed polymeric micelles have been prepared from aqueous solutions of poly(2-(dimethylamino)ethyl methacrylate)-block-poly(glyceryl methacrylate), PDMAEMA45-b-PGMA90, and poly(acrylic acid)-block-poly(acrylamide), PAA42-b-PAAm417, through complex coacervation of the oppositely charged blocks. Rather monodisperse, spherical aggregates are formed with a Rh = 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 1H 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.