The tuning of interfacial properties at selective and desired locations on the particles is of great importance to create the novel structured particles by breaking the symmetry of their surface property. Herein, a dramatic transition of both the external shape and internal morphology of the particles of polystyrene-b-poly(4-vinylpyridine) (PS-b-P4VP) was induced by precise positioning of size-controlled Au nanoparticle surfactants (Au NPs). The size-dependent assembly of the Au NPs was localized preferentially at the interface between the P4VP domain at the particle surface and the surrounding water, which generated a balanced interfacial interaction between two different PS/P4VP domains of the BCP particles and water, producing unique convex lens-shaped BCP particles. In addition, the neutralized interfacial interaction, in combination with the directionality of the solvent-induced ordering of the BCP domains from the interface of the particle/water, generated defect-free, vertically ordered porous channels within the particles. The mechanism for the formation of these novel nanostructures was investigated systemically by varying the size and the volume fraction of the Au NPs. Furthermore, these convex lens-shaped particles with highly ordered channels can be used as a microlens, in which the light can be concentrated toward the focal point with enhanced near-field signals. And, these particles can possess additional optical properties such as unique distribution of light scattering as a result of the well-ordered Au cylinders that filled into the channels, which hold great promise for use in optical, biological-sensing, and imaging applications.

Colloidal particles with controlled shape and internal structure have attracted great attention due to their novel morphologies and various potential applications. Among the diverse synthetic strategies toward anisotropically shaped polymer particles, facile and accurate engineering of such structures remains challenging. This review highlights the synthetic approaches to manipulate the shape of polymer particles driven by phase separation in emulsions upon solvent evaporation. And, special attention is given to the thermodynamic and kinetic principles of particle shape control, followed by detailed experimental examples and their applications. Major synthetic strategies for the preparation of nonspherical block copolymer (BCP) particles by evaporation of solvent from BCP‐containing emulsions are discussed as follows: engineering of i) interfacial properties of the confining emulsion droplets, ii) particle (or droplet) size, iii) segregation behavior of BCPs within the droplet, and iv) solvent‐induced BCP self‐assembly kinetics (i.e., solvent evaporation rate). Next, functionalized BCP particles produced by careful design of the chemical structures of polymer or by incorporation of functional additives into the polymer matrix are introduced. Finally, this review article aims to present the challenging issues associated with current methods and future directions for research in this field.

Shape and morphology of polymeric particles are of great importance in controlling their optical properties or self-assembly into unusual superstructures. Confinement of block copolymers (BCPs) in evaporative emulsions affords particles with diverse structures, including prolate ellipsoids, onion-like spheres, oblate ellipsoids, and others. Herein, we report that the evaporation rate of solvent from emulsions encapsulating symmetric polystyrene-b-polybutadiene (PS-b-PB) determines the shape and internal nanostructure of micron-sized BCP particles. A distinct morphological transition from the ellipsoids with striped lamellae to the onion-like spheres was observed with decreasing evaporation rate. Experiments and dissipative particle dynamics (DPD) simulations showed that the evaporation rate affected the organization of BCPs at the particle surface, which determined the final shape and internal nanostructure of the particles. Differences in the solvent diffusion rates in PS and PB at rapid evaporation rates induced alignment of both domains perpendicular to the particle surface, resulting in ellipsoids with axial lamellar stripes. Slower evaporation rates provided sufficient time for BCP organization into onion-like structures with PB as the outermost layer, owing to the preferential interaction of PB with the surroundings. BCP molecular weight was found to influence the critical evaporation rate corresponding to the morphological transition from ellipsoid to onion-like particles, as well as the ellipsoid aspect ratio. DPD simulations produced morphologies similar to those obtained from experiments and thus elucidated the mechanism and driving forces responsible for the evaporation-induced assembly of BCPs into particles with well-defined shapes and morphologies.

Confined assembly of block copolymers (BCPs) is receiving increasing attention due to the ability to create unconventional morphologies that cannot be observed in the corresponding bulk systems. This effect is further driven by the simplicity and versatility of these procedures for controlling the shape of particles prepared by 3D soft confinement of BCPs in emulsions. By taking advantage of a mobile emulsion interface, the one-step formation of nonspherical BCP particles through spontaneous deformation is possible with design principles and theoretical models for controlling shape/nanostructure now being established. This Viewpoint highlights strategies for shape tuning of BCP particles, currently accessible shapes, their controllability, and potential application. The emergence of 3D soft confinement of BCPs and related theory is overviewed with a focus on current strategies, types of nonspherical shapes achieved, and structure–property relationships for nonspherical BCP particles. Finally, the applications and future perspectives for these materials are discussed.

Click chemistry is one of the most powerful strategies for constructing polymeric soft materials with precise control over architecture and functionality. In this review, we provide a comprehensive summary of the state-of-the art for synthesizing functional polymers and their expanding range of applications. The synthetic and mechanistic aspects are discussed for key reactions that fulfill "click" requirements and their applications in construction of macromolecules with linear, branched, and other complex architectures are described.