Abstract. We report on the formation of polymeric micelles in water using triblock copolymers with a polyethylene glycol middle block and various hydrophobic outer blocks prepared with the precipitation method. We form micelles in a reproducible manner with a narrow size distribution. This suggests that during the formation of the micelles the system had time to form micelles under close-to-thermodynamic control. This may explain why it is possible to use an equilibrium self-consistent field theory to predict the hydrodynamic size and the loading capacity of the micelles in accordance with experimental finding. Yet, the micelles are structurally quenched as concluded from the observation of size stability in time. We demonstrate that our approach enables to prepare rather hydrophobic block copolymer micelles with tunable size and loading.

We have used the Scheutjens-Fleer self-consistent field (SF-SCF) method to predict the self-assembly of triblock copolymers with a solvophilic middle block and sufficiently long solvophobic outer blocks. We model copolymers consisting of polyethylene oxide (PEO) as solvophilic block and poly(lactic-co-glycolic) acid (PLGA) or poly(ǫ-caprolactone) (PCL) as solvophobic block. These copolymers form structurally quenched spherical micelles provided the solvophilic block is long enough. Predictions are calibrated on experimental data for micelles composed of PCL-PEO-PCL and PLGA-PEO-PLGA triblock copolymers prepared via the nanoprecipitation method. We establish effective interaction parameters that enable us to predict various micelle properties such as the hydrodynamic size, the aggregation number and the loading capacity of the micelles for hydrophobic species that are consistent with experimental finding.

Using self‐consistent field (SCF) theory, we studied the self‐assembly characteristics of polyurethane pre‐polymer dispersions in aqueous solutions. With a molecularly detailed model implementing the Scheutjens–Fleer discretization scheme, it is shown how the stability, equilibrium size, and internal structure of the (swollen) micelles in polyurethane (PU) dispersions depend on the chemical structure and the molecular composition of the charged pre‐polymer mixtures. The stability region of these micelles is found to increase when acid groups become deprotonated and when the ionic strength is lowered. Insight into the physical–chemical behavior of PU pre‐polymer dispersions is important for the subsequent process of film formation from the PU dispersions for the final coating properties.

A recently introduced DNA-bottlebrush system, which is formed by the co-assembly of DNA with a genetically engineered cationic polymer-like protein, is subjected to osmotic stress conditions. We measured the inter-DNA distances by X-ray scattering. Our co-assembled DNA-bottlebrush system is one of the few bottlebrushes known to date that shows liquid crystalline behaviour. The alignment of the DNA bottlebrushes was expected to increase with imposed pressure, but interestingly this did not always happen. Molecularly detailed self-consistent field calculations targeted to complement the experiments, focused on the role of molecular crowding on the induced persistence length lp due to the side chains and the cross-sectional width D of the molecular bottlebrushes. Both the thickness as well as the backbone persistence length drop with increasing protein-polymer bulk concentrations and dramatic effects are found above the overlap threshold. The flexibilisation is more significant and therefore the bottlebrush aspect ratio, lp/D, decreases with protein-polymer concentration. This loss in aspect ratio is yet another argument why molecular bottlebrushes rarely order in anisotropic phases and may explain why bottlebrushes are excellent lubricants.

Block copolymers composed of methacrylic acid (MAA) and methyl methacrylate (MMA) blocks are interesting candidates for replacing surfactants in emulsion polymerization methods. Here the synthesis and experimental characterization of well-defined PMAA–PMMA block copolymers made via RAFT polymerization are reported. It is shown that these block copolymers self-organize in water into micellar spherical or cylindrical structures or into highly size disperse structures (probably vesicles) in aqueous salt solutions upon increasing the pH. The physical properties of the polymer dispersions depend on the self-organization morphology which is determined by the diblock copolymer PMAA and PMMA block lengths. The relation between diblock copolymer block lengths and the self-organized structures is rationalized using self-consistent field theory (SCFT). Theoretically predicted self-assembled structures of MAA x –MMA y block copolymers are compared with the results obtained from experiments. Size and morphology of the self-assembled structures are in good agreement with SCFT.