We have studied structure formation in a confined block copolymer melt by means of dynamic density functional theory. The confinement is two dimensional, and the confined geometry is that of a cylindrical nanopore. Although the results of this study are general, our coarse-grained molecular model is inspired by an experimental lamella-forming polysterene-polybutadiene diblock copolymer system [K. Shin et al., Science 306, 76 (2004)], in which an exotic toroidal structure was observed upon confinement in alumina nanopores. Our computational study shows that a zoo of exotic structures can be formed, although the majority, including the catenoid, helix, and double helix that were also found in Monte Carlo nanopore studies, are metastable states. We introduce a general classification scheme and consider the role of kinetics and elongational pressure on stability and formation pathway of both equilibrium and metastable structures in detail. We find that helicity and threefold connections mediate structural transitions on a larger scale. Moreover, by matching the remaining parameter in our mesoscopic method, the Flory-Huggins parameter χ, to the experimental system, we obtain a structure that resembles the experimental toroidal structure in great detail. Here, the most important factor seems to be the roughness of the pore, i.e., small variations of the pore radius on a scale that is larger than the characteristic size in the system.

The solubilization mechanism of lipid membranes in the presence of Triton X-100 (TX-100) is investigated at molecular resolution using hybrid particle field–self consistence field simulations.

Nanoadditives alter the properties of pure block copolymers, through an interplay of entropic, enthalpic and kinetic factors at competing length and time scales. A fundamental understanding of these factors is considered decisive for taming block copolymer nanocomposites, since even modest changes in design parameters can impact the final material. At the same time, analytical and computational approaches have not yet reached the maturity required for an integrated study of all relevant aspects. Heterogeneity, local irregularities and dynamic behavior—these are the most challenging issues facing theory and simulations in the quest for rational design. In this review, we discuss the state of mesoscopic modeling for block copolymer nanocomposites, and cover relevant literature from at least the last five years, during which developments have taken off.

We have followed the reorientation kinetics of various block copolymer solutions exposed to an external electric DC field. The characteristic time constants follow a power law indicating that the reorientation is driven by a decrease in electrostatic energy. Moreover, the observed exponent suggests an activated process in line with the expectations for a nucleation and growth process. When properly scaled, the data collapse onto a single master curve spanning several orders of magnitude both in reduced time and in reduced energy. The power law dependence of the rate of reorientation derived from computer simulations based on dynamic density functional theory agrees well with the experimental observations. First experiments in AC electric fields at sufficiently high frequencies confirm the notion that the reorientation process is dominated by differences in the dielectric constants rather than by mobile ions.

The first three-dimensional (3D) simulation of meso-phase formation in a specific polymer system—55% aqueous solution of the triblock polymer surfactant $(\mathrm{EO}{)}_{13}(\mathrm{PO}{)}_{30}(\mathrm{EO}{)}_{13}$ —under simple steady shear is performed. The method is based on dynamic mean-field density functional theory. The hexagonal phase is investigated. The simulations reproduce recent experimental observations on the same polymer system.