Janus-like spheres, disks, rings, cylinders, and vesicles from the self-assembly of mixture of AB and BC diblock copolymers in A- and C-selective solvents

Abstract

Janus particles with two different compartments have enormous potential as building blocks of hierarchically multifunctional nanomaterials. One of the most versatile and powerful methods to fabricate Janus micelles is through the solution-state self-assembly of block copolymers. In this study, we applied the Monte Carlo simulation to study the self-assembly of a AB/BC diblock copolymer mixture in A- and C-selective solvents. Our simulations predicted a variety of novel Janus micelles, which include Janus-like cylinders, lamellas, vesicles, and rings, all of which were self-assembled from amphiphilic A₄B₆/B₆C₄ copolymers. The effects of control parameters, which include the solvent quality for solvophobic B blocks (ε_BS) and the incompatibility between the solvophilic A and C blocks (ε_AC), on the formation of Janus micelles were examined, and a generic phase diagram in ε_BS × ε_AC was constructed. The phase diagram demonstrates that the micellar shape mainly depends on ε_BS, whereas the formation of the Janus architecture is controlled by ε_AC. Moreover, the formation pathways of the Janus lamella, vesicle, and ring were investigated and their formation mechanisms were investigated.