Hierarchical self-assembly offers elegant and energy-efficient bottom-up strategies for the structuring of complex materials. For block copolymers, the last decade witnessed great progress in diversifying the structural complexity of solution-based assemblies into multicompartment micelles. However, a general understanding of what governs multicompartment micelle morphologies and polydispersity, and how to manipulate their hierarchical superstructures using straightforward concepts and readily accessible polymers remains unreached. Here we demonstrate how to create homogeneous multicompartment micelles with unprecedented structural control via the intermediate pre-assembly of subunits. This directed self-assembly leads to a step-wise reduction of the degree of conformational freedom and dynamics and avoids undesirable kinetic obstacles during the structure build-up. It yields a general concept for homogeneous populations of well-defined multicompartment micelles with precisely tunable patchiness, while using simple linear ABC triblock terpolymers. We further demonstrate control over the hierarchical step-growth polymerization of multicompartment micelles into micron-scale segmented supracolloidal polymers as an example of programmable mesoscale colloidal hierarchies via well-defined patchy nanoobjects.

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We performed theoretical and experimental investigations of dilute solutions of micelles of neutral amorphous diblock copolymers in selective solvents. The ranges of thermodynamic stability of spherical, cylindrical, and lamellar morphologies along with the equilibrium sizes and aggregation numbers of micelles are calculated and measured. For high molecular weight copolymers it is shown that the sphere-to-cylinder transition as well as precipitation of the micelles associated with cylinder-to-lamella transition occurs when aggregates have a crew-cut structure with the thickness of the corona smaller than the radius of the core. Similar to starlike micelles with corona larger than the core, the equilibrium parameters of crew-cut micelles are determined by the balance between the free energy of the corona and the surface energy of the core. The elastic free energy of the core remains small compared to the corona and surface free energies; however, it determines the transitions between different morphologies. The theoretical predictions including the existence of crew-cut spherical micelles, the range of stability of cylindrical micelles, and the significance of the contributions of the logarithmic corrections to scaling are in good agreement with experiments on polystyrene-polyisoprene block copolymer micelles in heptane, a selective solvent for the polyisoprene block.

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In this paper we use the polymer adsorption theory of Scheutjens and Fleer to describe polymer brushes at spherical and cylindrical surfaces that are immersed in a low molecular weight solvent. We analyze the volume fraction profiles of such brushes, focusing our attention on spherical brushes in athermal solvents. These are shown to generally consist of two parts: a power law-like part and a part that is consistent with a parabolic potential energy profile of the polymer segments. Depending on the curvature of the surface, one of these two parts is more important, or may even dominate completely. We especially consider the distribution of the free end segments and the possible existence of a "dead zone" for these segments. Such a dead zone is actually found and is seen to follow a scaling law in the case of large curvatures. Furthermore, the effect of diminishing the solvent quality is considered for both the total volume fraction profile and the distribution of the end segments.