cyclic voltammograms were taken for these two carbons by varying the scan rate from 5 mV/s to 50 mV/s, the SNU-2 carbon kept the rectangular-shape up to a scan rate of 20 mV/s (Fig. 5b, solid line). In contrast, the MSC-25 carbon showed a deformed cyclic voltammogram at a scan rate of 10 mV/s and a completely collapsed one at a scan rate of 20 mV/s (Fig. 5b, dotted line). A detailed discussion on the electrochemical studies of the material will be presented in a forthcoming paper.In conclusion, we have made a new high surface area mesoporous carbon using Al-HMS as a template. From this research we discovered that the pores of HMS are 3D interconnected, unlike the originally proposed disordered hexagonal structure. The EDLC performance of the carbon material was superior to the commercially available carbon MSC-25 due to improved mesoporosity. The CV of the mesoporous carbon showed ideal rectangular shapes at a high scan rate of 20 mV/s.

Spin-coated films of an ethylhexyl derivative of polyfluorene can be converted on a pretreated polyimide substrate into highly oriented films by annealing in the liquid crystalline state. Together with improving orientation segregation of the wormlike molecules with respect to chain lengths and lamella formation proceeds. End groups are preferentially assembled in interlamellar regions. This morphological feature is thought to influence all measurements of intrinsic properties of polyfluorene films with similar histories. Electron diffraction patterns of the film are identical with X-ray fiber diagrams of fibers drawn from the melt and annealed in the liquid crystalline state. The experimental data show that the polymer molecules adopt a helical (5/q) conformation, packing in a trigonal unit cell. Molecular modeling based on ab initio MO calculations have been carried out to obtain independent estimates of chain geometry and conformation. These calculations are more in favor of a 5/2 rather than a 5/1 helix, with the argument of the observed packing of the individual PF chains and a plausibly low torsion angle of adjacent fluorene building blocks only for a 5/2 helix.

Monodisperse polyphenylene dendrimers up to the fourth generation were synthesized using a divergent growth protocol. By varying the core, dendrimers with dumbbell-, tetrahedral- and propeller-like structures were synthesized. Because of the high-density packing of benzene rings within their branches, these dendrimers are stiff and thus shape persistent. To obtain these dendrimers with a globular shape, a 4-fold (A4B) dendrimer building unit was introduced. In this case, monodisperse dendrimers are obtained only up to the second generation due to the significantly increased density of benzene rings within the structure. For structure elucidation methods, like MALDI−TOF mass spectrometry, NMR spectroscopy, GPC, VPO, TGA, and DSC were used. Dendrimers of the third and fourth generations were visualized by transmission electron microscopy.

A series of amphiphilic diacetylene monocarbonic acids was synthesized, and their ability to form monolayers at the air–water interphase was investigated. Acids with total number of C atoms ≥20 and mp >45°C form surface states suitable to be used for buildup of multilayers by the Langmuir–Blodgett technique. Using the LB technique, multilayers of defined thickness were built up on quartz substrates. The multilayers were polymerized by exposure to a UV light source according to the mechanism of solid‐state polymerization of diacetylenes without destruction of the layer structure and with retention of the packing in the individual layers. Thus well‐defined polymer multilayers were obtained. The monomer and polymer multilayers were characterized by UV spectra, x‐ray small‐angle diffraction, and interference microscopic and electron microscopic techniques. The polyconjugated backbones of the polymer chains are all stretched out in the plane of the substrate but not over macroscopic dimensions because the multilayers have a crystalline domain structure. The polymer multilayer films are quite stable under ambient conditions.

A series of chirally substituted poly (p-phenyleneethynylene) copolymers was prepared by alkyne metathesis of mixtures of two different 2,5-dialkyl-1,4-dipropynylbenzenes. One of the monomers was the chiral bis-2,5-(S)-3,7-dimethyloctyl-1,4-dipropynylbenzene, and the second one was an achiral dipropynyl monomer. If the content of chiral monomer is 25-50 mol %, unusually large chiroptical effects, that is, optical dissymmetries, result in absorption (g = -0.38) and emission (g = -0.19) of these copolymers. The large dissymmetries can be explained by a supramolecular ordering of the PPEs into stranded features that are visualized by dark-field transmission electron microscopy. The strands of chirally substituted PPEs display a striated structure that suggests that the whole feature is a single chirally twisted crystallite.

The solid-state structures of a series of 2,5-dialkyl-substituted poly(p-phenyleneethynylene)s (PPEs 4, R = hexyl, dodecyl, isopentyl, ethylbutyl, ethylhexyl, H) and of 2,5-didodecyl(1,4-phenylenebutadiynylene) were investigated by X-ray powder and electron diffraction. In addition, X-ray single-crystal structures of the monomeric (1,4-dipropynyl-2,5-dialkyl)benzenes were obtained and compared to the structures of the corresponding polymers. In the case of the ethylhexyl-substituted PPE, the packing of the monomer resembles that of the polymer in the solid state. All of the examined PPEs show lamellar morphologies, in which the extended geometry of the side chains determines the value of the lamellar spacing obtained by powder diffraction. A second d value, which could be obtained for all samples represents the π−π-stacking distance of the main chains. This distance is around 3.8 Å, a typical value for stacking of aromatic systems. It implies strong electronic interaction of the chromophoric backbones, leading to the observed sharp aggregate band in CHCl3/MeOH solutions and in thin films. From the scattering data, staggered packing of the benzene rings and the phenyleneethynylene main chains in PPEs 4 was inferred. This packing avoids repulsive electrostatic interactions between adjacent conjugated phenyleneethynylene chains and at the same time leads to optimal packing of the side chains.

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In an attempt to study which factors determine the transferability of monolayers of preformed polymers from the air-water interface onto substrates we investigated flexible polymers (poly(octadecylmethacrylates) (PODMAs)) and 0t-helical polymers (polyglutamates). Pressure-area isotherms show the formation of a liquid-analogous state which depends on temperature and side chain "impurity". Ymode Langmuir-Blodgett multilayers of these polymers can be formed with a constant transfer ratio under conditions at which a more or less liquid-analogous state exists. Polarized IR spectra suggest that the polyglutamate a helices in the multilayer are oriented with the main axis parallel to the transfer direction and that carbon Side chains are practically randomly oriented around the a-helical cylinder. In PODMA multilayers the side chains are perpendicular to the film. In both cases the sidechains seem to interdigitate.