Hyperbranched poly(arylene oxindole)s with a degree of branching of 100% for the construction of nanocontainers by orthogonal modification

Hyperbranched polymers with a degree of branching of 100% have been prepared and converted into different types of unimolecular micelle-like structures. The polymers were obtained by acid catalyzed polycondensation of an isatin-based AB2 monomer, prepared without using toxic organometal reagents or extensive chromatographic purification. The molar masses as determined by SEC relative to linear PS standards were strongly underestimated as compared to absolute data determined by MALLS. This could be accounted for by the densely branched structure and the formation of intramolecular hydrogen bonds. The hyperbranched scaffolds were converted into unimolecular micelle-like structures in two ways. In a first approach, Iona alkyl chains were introduced at the terminal units and carboxyl groups at the dendritic units. The resulting macromolecules were soluble in apolar solvents and able to bind polar dyes. Alternatively, the terminal units could be converted into quaternary ammonium salts. leading to water-soluble macromolecules binding apolar BODIPY dyes.