Ring-like curved surfaces

SSL theory for diblock copolymers confined in ring-like curved surfaces... 

Figure 30 shows the symmetrical concentric-ring barrel structure (A-B-A)m confined between two ring-like curved surfaces (cylinders). It is assumed that the fringe thickness is the same for both the exterior and interior layers, while that of the middle layers is nearly twice in size regardless of A domain or B domain. This assumption has been proved to be valid via MC simulation mentioned above. 

In this work, a framework of the SSL theory for diblock copolymer melts confined in ring-like curved surfaces has been proposed. When the curvature approaches to zero, it reduces to the well-known SSL theory for the parallel lamellar phases. In the case of the equal confined thickness to the exterior radius, it can also be extended to the system with a nanopore confinement. Moreover, the Helmholtz energy of the concentric cylinder barrel, sector column and CMSC phases in 2D confinements based on this SSL theoretical framework can be evaluated in the convenient manner. The calculated results show that the diblock copolymer melts exhibit a layer-type transition with a similar mechanism, regardless of ring-like curved surfaces, planar surfaces, and nanopores. 

Figure 2 compares the UV-visible spectra of AW-Ph-HMM and CW-Ph-HMM (curves a and b, respectively), after contact with iodine vapours and outgassing at room temperature. As it concerns the material with crystal-like walls, no peaks related to I2 molecules are observed. Since surface specific areas of the two materials are comparable, this finding suggests a lower availability of phenyl rings for the crystal-like walls material, where, following the model reported in [7], the aromatic moieties lie perpendicularly with respect to the pore surface. 

Yet, several classes of non-planar aromatic compounds are also known. In most cases, such compounds contain fused benzene-like ring moieties that are bent out-of-plane by steric constraints. Molecular belts [45], pyrenophane derivatives [46, 47] and contracted porphyrinoids [48] are representative examples of these systems. In general, the study of non-planar aromatic compounds opens new opportunities for developing molecular devices with potential application in materials science. For example, porphyrinoids have recently attracted significant interest, as their curved aromatic stmctures show concave or convex n surfaces able to interact in various ways with electroactive compounds [48]. 

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