Liquid‐Crystallization‐Driven Self‐Assembly toward Uniform Multi‐Morphology Fried‐Egg‐Like Nanostructures

Abstract

Liquid‐crystallization‐driven self‐assembly (LCDSA) has recently emerged as an efficient strategy to create uniform one‐dimensional (1‐D), 2‐D and 3‐D nanostructures in a controlled manner. However, the examples of generation of uniform multi‐morphology nanostructures from solution self‐assembly of one single polymer sample are rare. Herein, we report the first example of preparation of multi‐morphology fried‐egg‐like nanostructures consisting of an inner spherical/bowl‐like core of uniform size and platelets protruded from the core by LCDSA of PAMAM‐Azo6 (PAMAM = polyamidoamine, Azo = azobenzene) in methanol. It is disclosed that the different aggregation rates for PAMAM‐Azo6 with varying contents of Azo units spontaneously separated nucleation and growth stages, which led to the formation of inner spherical/bowl‐like cores (“seeds”) firstly, followed by the formation of platelets protruded from the edges of inner core to give “imperfect” fried‐egg‐like nanostructures. Additional annealing of initially formed “imperfect” fried‐egg‐like micelles will promote the rearrangement of Azo units to give thermodynamically‐favored “perfect” fried‐egg‐shaped micelles with a uniform dimension both in the core and whole structure. This work not only provides an efficient strategy to create uniform multi‐morphology fried‐egg‐shaped nanostructures, but also reveals the essential impact of aggregation kinetics of liquid‐crystalline‐coil BCPs in the formation of multi‐morphology nanostructures.