The surface morphology of a symmetric poly(styrene-block-butadiene-block-methyl methacrylate) triblock copolymer (PS-b-PB-b-PMMA) with 6 wt % PB has been investigated by tapping mode scanning force microscopy (SFM). The results are compared to the bulk morphology as determined by transmission electron microscopy (TEM). In solvent-cast films PS/PMMA lamellae are formed, which are oriented nearly perpendicular to the free surface. Like in the bulk, also at the free film surface polybutadiene spheres are located at the lamellar PS/PMMA interface. However, contrary to the bulk, the surface morphology includes a large number of defects such as curved lamellar and disclinations, and the lamellar long period is doubled, from 42.7 ± 0.5 nm in the bulk to 85 ± 5 nm at the free surface, indicating a surface reconstruction. The double spacing can be explained by a surface buckling in registry with the underlying PS/PMMA lamellae. The composition of the outermost surface layer is discussed.

In this paper, I explore automobility as the dominant type of contemporary everyday mobility. I critically review recent attempts to conceptualise the social role of cars and subsequently suggest a three-dimensional model to theorise automobility further as a modern mobility paradigm. This theory of automobility assigns central importance to the subjects, the vehicles, and the spatiotemporalities that are involved in, and produced by, the car-system. For the purpose of outlining the content and internal dependencies of this three-dimensional model, I make use of theoretical assumptions gleaned from transport geography, modernisation theory, as well as the sociology of technology. Furthermore, I argue that a somewhat orthodox form of automobilisation has become reflexive in the course of a growing public recognition of the inherent threats of the car to culture and nature. Under reflexive automobilisation almost all ‘auto-subjects’ are engaged in defining, interpreting, and responding to ‘auto-risks’. They do not necessarily do this, however, in a self-critical fashion. Instead of fostering the rise of a different, postautomotive mobility paradigm, their responses often merely lead to a reproduction of traditional ‘auto-scapes’.

Block copolymers show microphase separation into ordered microdomains if the product of the overall degree of polymerization P , and the Flory-Huggins interaction parameter x between the constituent blocks exceeds a critical value 1-4). Spherical, cylindrical, lamellar and bicontinuous double-diamond morphologies were observed in linear AB and ABA, and (AB), star block copolymers'-"). The details of the microphase morphologies depend on the composition, the molecular weight and the casting solvent l 2 -I 5 ) . Additional structural variation can be realized in mixtures of AB diblocks of different molecular weight 16).ABC block copolymers consisting of three chemically different immiscible polymeric components offer the opportunity to create new multiphase morphologies 17-24). Generally, the morphologies which are expected in ABC systems are composed of the basic structural features known from AB(A) block copolymers. Morphological studies on symmetric ABC triblock copolymers show "three-layered" lamellar, "ball in the box" spherical or "rod in the tube" cyclindrical morpholog i e~" -~' ) .Mogi et al. have recently reported on a highly ordered tricontinuous double-diamond morphology in a P(1-b-S-b-VP) triblock copolymer 21*22) (I = isoprene, S = styrene, VP = vinylpyridine). Thomas et al. showed that even morphologies with non-uniform curvature may be realized in an P(S-6-I-b-VP) system23).In addition to AB(A) block copolymers ABC systems offer the opportunity to create ordered morphologies containing simultaneously mesoscopic structures of different dimensionality. In a previous work we demonstrated the formation of a morphology consisting of A/C lamellae with B cylinders arranged regularly at the A/C interface24) in a polystyrene-block-poly(ethy1ene-co-1 -butene)-block-poly(methy1 methacrylate) (P(S-b-EB-b-MMA)) block copolymer, containing 17 wt.-Yo of EB (symmetric with respect to S/MMA). Surprisingly, the further reduction of the size of the hydrogenated polybutadiene center block resulted in a morphology in which PS cylinders covered by PEB domains are imbedded in a PMMA matrix.In the present communication we will discuss the morphology of the corresponding polystyrene-block-polybutadiene-bZock-poly(methy1 methacrylate) block copolymer, which completely differs from the hydrogenated analogue. Selective staining will be used to analyze the location of the short PB block at the PS/PMMA interface.

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