The domain structure in thin films of an immiscible polystyrene/poly(methyl methacrylate) (PS/PMMA) blend was studied after spin-casting from a common solvent. Atomic force microscopy (AFM) combined with selective dissolution was used to obtain three-dimensional information on the domain morphology in thin films. Three different common solvents and three different substrate surfaces were studied. Distinct differences in the thin film domain structure and surface topography are observed depending on the substrate surface energy and the solubility of the two polymers in the three solvents. The topographic modulation can be explained by a different rate of solvent evaporation during spincoating for the two phases. The normal and lateral organization of the phase-separated domains is governed by a complex interplay between preferential aggregation of one phase at the substrate and phase segregation in the film. Additionally, some of the results suggest that a dewetting process may be involved in the domain formation. The structures obtained after spin-casting are far from thermodynamic equilibrium. The equilibration of the films during annealing depends strongly on the phase morphology, and long-lived metastable configurations are found.

We have experimentally determined a phase diagram for cylinder-forming polystyrene-block-polybutadien-block-polystyrene triblock copolymer in thin films. The phase behavior can be modeled in great detail by dynamic density functional theory. Deviations from the bulk structure, such as wetting layer, perforated lamella, and lamella, are identified as surface reconstructions. Their stability regions are determined by an interplay between surface fields and confinement effects.

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Atom transfer radical polymerization (ATRP) was applied to the synthesis of amphiphilic cylindrical polymer brushes by using the “grafting from” technique. The procedure included the following steps:  (1) ATRP of 2-hydroxyethyl methacrylate (HEMA) gave well-defined poly(HEMA), (2) subsequent esterification of the pendant hydroxy groups of poly(HEMA) with 2-bromoisobutyryl bromide yielded a polyinitiator, poly(2-(2-bromoisobutyryloxy)ethyl methacrylate (PBIEM), (3) ATRP of various monomers (tert-butyl acrylate, or styrene) using PBIEM as polyinitiator yielded cylindrical brushes with homopolymer side chains, (4) addition of a second monomer (styrene or tert-butyl acrylate) formed the cylindrical brushes with diblock copolymer side chains (core−shell cylinders), and (5) hydrolysis of the poly(tert-butyl acrylate) (PtBA) block of the side chains to poly(acrylic acid) (PAA) formed amphiphilic core−shell polymer brushes. By using this technique, well-defined core−shell cylindrical polymer brushes with polystyrene (PS), PtBA, PS- b-PtBA, PtBA- b-PS, PS-b-PAA, or PAA-b-PS as side chains were successfully synthesized. The molecular weights and radii of gyration of the polymer brushes were obtained by static light scattering in THF. The absence of inter/intra-macromolecular coupling reactions during ATRP synthesis was confirmed by GPC, NMR, and MALDI−TOF analyses of the side chains and scanning force microscopy (SFM). Single wormlike unimolecular nanocylinders are clearly visualized on a mica surface while aggregates are usually observed on a SiO x surface. The brushes with PS-b-PtBA side chains were hydrolyzed to PS-b-PAA side chains forming unimolecular wormlike micelles. These unimolecular micelles showed a unique response to solvent quality, as indicated by 1H NMR and dynamic light scattering.