Figure 5. Convective assembly processes for the two-dimensional crystallization of colloids. (a) Vertical deposition process. (b) Horizontal deposition process. (c) Typical problems arising from convective assembly processes as reported by Dimitrov et al. Reprinted with permission from ref 198.

Stimuli-responsive polymers are the subject of intense research because they are able to show responses to various environmental changes. Among those stimuli, light has attracted much attention since it can be localized in time and space and it can also be triggered from outside of the system. In this paper, we review light-responsive block copolymers (LRBCs) that combine characteristic features of block copolymers, e.g., self-assembly behavior, and light-responsive systems. The different photo-responsive moieties that have been incorporated so far in block copolymers as well as the proposed applications are discussed.

The influence of various experimental parameters on the vertical deposition and structure formation of colloidal crystals on chemically patterned surfaces, with hydrophilic and hydrophobic areas, was investigated. The pattern dimensions range from about 4 to 400 microm, which is much larger than the individual particle size (255 nm), to control the microscopic crystal shape rather than influencing the crystal lattice geometry (as achieved in colloidal epitaxy). The deposition resolution and selectivity were tested by varying the particle concentration in the suspension, the substrate withdrawing speed, pattern size and orientation, and wetting contrast between the hydrophilic and hydrophobic regions. The evolution of colloidal crystal thickness with respect to the pattern dimensions and deposition parameters was further studied. Our results show that the pattern size has a rather strong influence on the deposited number of colloid layers and on the crystal quality. Better results are obtained when the lines of a stripe pattern are oriented parallel to the withdrawing direction rather than perpendicular. The deposition resolution (defined as the minimum feature size on which particles can be deposited) depends on the wetting contrast and increases with lower average hydrophobicity of the substrate.

Supramolecular copolymers have become of increasing interest in recent years for the search of new materials with tunable properties. In particular, metallo‐supramolecular block copolymers—copolymers in which the blocks are linked together by a metal–ligand complex—have seen important progresses, allowing better control over the synthetic strategies for various architectures, and providing a better understanding of the parameters governing their self‐assembly. We review here recent developments on the synthesis and self‐assembly of such materials achieved in this field.

We investigate the time-dependent linear viscoelastic behavior of amine and alkaline metal-neutralized carboxy−telechelic 1,4-polybutadiene, and compare it with the acid precursor as well as an ester end-modified version. The ionic groups form aggregates with a aggregate spacing period around 85 Å, containing about 90 chain-ends. Rheological tests highlight the existence of a strongly time-dependent terminal relaxation and an intermediate frequency relaxation, which can be assimilated to a glass transition of the ionic aggregates and their immediate environment. The terminal relaxation time after neutralization with alkali metal increases by up to 7 decades. Contrary to previously published results, this time is found to be a strongly increasing function of metal atomic mass for the equilibrated structures. The discrepancy can be rationalized by analyzing the annealing time dependence of the phenomena. Earlier studies did not report on truly equilibrated systems. While the main phase glass transition is hardly affected by neutralization, the temporary network formed by the ionic associations shows a very high and ion-dependent temperature sensitivity. Moreover, a failure of the time−temperature superposition principle is found at intermediate temperatures or frequencies, because the terminal and intermediate frequency relaxations do not follow the same temperature dependence.

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This outlook paper focuses on micelles formed by ABC triblock copolymers (triblock terpolymers) and related systems resulting from mixtures of diblock copolymers. Micelles with different internal structure such as micelles with a heterogeneous core and a homogeneous corona or micelles with a homogeneous core and a mixed corona are presented. More complex nanoobjects such as vesicles and Janus particles are also reviewed. Finally, potential applications of these objects are discussed.