Controlled Self-Assembly of Amphiphilic Random Copolymers into Folded Micelles and Nanostructure Materials

In this review, we report controlled self-assembly systems of amphiphilic random copolymers in aqueous or organic media and the solid state to produce folded micelles, related nanoaggregates, vesicles, and microphase separation materials. The key features of random copolymer self-assemblies are 1) self-folding of polymer chains, 2) precision self-assembly of side chains, and 3) dynamic self-sorting and selective recognition. Typically, random copolymers bearing hydrophilic poly(ethylene glycol) and hydrophobic alkyl groups folded into small unimer micelles (~10 nm) via the association of the hydrophobic groups in water. Importantly, those random copolymers afforded precision intermolecular self-assembly into multichain micelles; the size, aggregation number, and thermoresponsive properties can be controlled as desired by tuning their molecular weight, composition, and side chains. The binary mixture of different random copolymers further self-sorted via chain exchange in water to simultaneously form discrete micelles. Namely, amphiphilic random copolymers can dynamically recognize themselves in complex media like natural biomolecules and proteins. Amphiphilic random copolymers opened new ways to create self-assembled materials with well-defined nanostructures and compartments, dynamic recognition properties, and functions.