Confined self‐assembly of block copolymers in emulsion droplets: Preparation, shape and internal structure, and applications

Abstract Confined assembly of block copolymers (BCPs) in emulsion droplets receives considerable attention since self‐assembly in flexible geometry pioneers an efficient yet promising route to prepare unconventional polymer materials that cannot be acquired in the bulk state or solution. The deformability and interfacial property regulation of the soft emulsion droplets offer tremendous potential for the design and construction of BCP nanoparticles with desired shape and internal nanostructures. This review summarizes the recent developments of BCP assembly behavior in three‐dimensional (3D) soft oil emulsion droplets, including preparation methods, shape and internal structure control, as well as advanced applications of the generated BCP materials. Typical experimental parameters and post processes, including intrinsic property of BCPs, surfactant property, confinement degree, interfacial instability, additives, evaporation rate, post‐annealing, and disassembly, that have significant influence on the precise control and regulation of emulsion interface properties and the prepared assembly structures are well systematically summarized. Finally, the challenges and further perspective in this area are presented.