Dendritic-linear miktoarm star polymers from orthogonal protected initiators

Abstract

The synthesis of miktoarm dendritic-linear star copolymers in a tandem "core-in"/"core-out" approach is described. This synthetic approach is enabled by rational design and synthesis of an orthogonal protected compound containing six sites arranged in an alternating fashion for attachment of dendrimers and atom transfer radical polymerization of linear polymer chains. The judicious choice of the dendrimer surface functionality coupled with the properties of the monomer used in the linear chain allows the creation of amphiphilic molecules capable of supramolecular assembly. 1H NMR and SEC studies of the block copolymers confirmed that the targeted polymer structures were achieved with low polydispersities and good yields. The nature and the size of the arms and dendrons had a significant influence on the hydrodynamic radii (Rh) measured by dynamic light scattering. Some of these macromolecules microphase-separated after annealing.