Novel Amphiphilic Multiarm, Starlike Coil–Rod Diblock Copolymers via a Combination of Click Chemistry with Living Polymerization

A series of novel amphiphilic 21-arm, starlike diblock copolymers, poly(acrylic acid)- b -poly(3-hexylthiophene) (PAA- b -P3HT), based on β-cyclodextrin (β-CD) with well-defined molecular architectures and ratio of two chemically distinct blocks were prepared, for the first time, via a combination of quasi-living Grignard metathesis method (GRIM), click reaction, and atom transfer radical polymerization (ATRP). The starlike PAA- b -P3HT diblock copolymers consist of hydrophilic coil-like PAA cores and hydrophobic rodlike P3HT shells with narrow molecular weight distribution and well-defined molecular weight of each block. Owing to the compact structure, the amphiphilic starlike PAA- b -P3HT formed a unimolecular micelle. Emulsion based on these novel amphiphilic starlike, coil–rod diblock copolymers were readily produced by cross-linking hydrophilic coil-like PAA cores with a bifunctional cross-linker, ethylenediamine.