Self-assembly of Block Copolymers Under 3D Confinement: Toward Nanostructured Particles

Compared to self-assembly of block copolymers in bulk, self-assembly of block copolymers under confinement, especially three-dimensional (3D) confinement, can lead to various unexpected microphase-segregated structures, which not only opens a door for deep investigation of the phase behavior of block copolymers, but also offers a precise and powerful route for the preparation of nanostructured particles. A rich variety of unique nanostructured particles can be generated through regulating the confinement effect, interfacial interaction, and volume fraction of each block, which pose great potentials in nanoscience and nanotechnology. In this review, we will first highlight several recent advances in preparing block copolymer nanostructured particles based on 3D confinement theoretically and experimentally. Two types of 3D confinement assembly, e.g., hard and soft confinement, are both discussed. Compared to the 3D hard confinement which has fixed confining geometry and space size, 3D soft confinement assembly are more flexible, and the shape and dimension of the block copolymer particles can be tailored by varying either the internal or external conditions. The functionalization and potential applications of the nanostructured particles will then be discussed, followed by the summary and outlook of this unique field.