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A few concepts related to the development of surface structure and how it can affect the appearance of automotive coatings are discussed. These concepts include flow and leveling, substrate telegraphing, gradient of drying or curing, and inter-layer compatibility in multi-layer systems. While flow and leveling is essential to achieve excellent coating appearance, volume shrinkage is the driving force for telegraphing substrate texture. Gradients of cure (both intra-layer and inter-layer) and wrinkle formation are the fundamental mechanisms for surface structure formation in low-bake systems. For multi-layer systems, inter-layer ingredient migration and mismatch of cure rates between the neighboring layers can disrupt the interfacial structure and create structures on the topmost surface, typically a clearcoat. For systems where multiple layers are sprayed wet-on-wet-on-wet (3-W) and baked simultaneously, all the factors above influence appearance. To achieve the best system appearance for high temperature baking conditions, an addition-reaction crosslinking chemistry is superior to condensation crosslinking chemistry. This is due to addition-reaction chemistry providing lower overall volume shrinkage and a prolonged flow and leveling period based on the slower cure rate of the system used in this study.

The introduction of the CF3 group on the C9 atom in quinidine can significantly increase the conformational interconversion barrier of the cinchona alkaloid scaffold. With this modification the conformational behavior of cinchona alkaloids in various solvents can be conveniently investigated via (19)F NMR spectroscopy. Based on the reliable conformational distribution information obtained, the accuracy of both theoretical (PCM) and empirical (Kamlet-Taft) solvation models has been assessed using linear free energy relationship methods. The empirical solvation model was found to provide accurate prediction of solvent effects, while PCM demonstrated a relatively low reliability in the present study. Utilizing similar empirical solvation models along with Karplus-type equations, the conformational behavior of quinidine and 9-epi-quinidine has also been investigated. A model SN2 reaction has been presented to reveal the important role of solvent-induced conformational behavior of cinchona alkaloids in their reactivity.

Structurally well-defined C4F9, C7F15, C10F21 and C13F27 end-functionalized polystyrene (RF-PS) and polybutylmethacrylate (RF-PBMA) were prepared by Atom Transfer Radical Polymerization using RF–tagged initiators. Blends (1/1 wt/wt) of these polymers were studied by differential scanning calorimetry (DSC), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), optical transmittance(OT), electron microscopy (TEM) and optical transmittance (OT). The RF-PS/RF-PBMA blends having molecular weights of 20,000 and C7F15 or larger end groups, were optically transparent. The AFM micrographs show crater, necklace and other RF mediated morphologies typically at the submicron scale. TEM images of the corresponding blends show assembly of elongated domains with sizes in the micron or nanometer scales depending on MW and RF size. Thus, above about 3 wt percent RF content only microphases (m) are observed while below 1.8 wt percent only macrophases (M) are seen. A semi-quantitative “phase diagram” of the blends shows that lower MWs and longer RF groups improve phase compatibilities.

In cinchona alkaloid-based scaffolds, hindered CF3 rotations have been observed. The variation in barrier heights for the CF3 rotations is controlled by the corresponding entropic changes when the substituents are changed from an allyl to a bulky 9-methylanthracenyl group. Quantum chemical and experimental studies have shown that the noncovalent C3′[BOND]H1⋅⋅⋅F[BOND]C interactions in the studied cases possess a weak hydrogen bonding-like

The trifluoromethyl substituent has been incorporated into quinidine as a conformational stabilizer and a probe to provide straightforward insight into the conformational behavior of cinchona alkaloids. By significantly decreasing the rotation rate of the quinoline-carbinol bond, the relatively bulky CF(3) group enables the NMR signals of the syn and anti conformers to be differentiated at room temperature. In addition to the stabilizing effect, the introduction of the fluorinated moiety also facilitates the application of (19)F NMR spectroscopy, thereby allowing conformational studies under various conditions without the use of deuterated solvents.

C @ S nanocomposites based on mesoporous hollow carbon capsules were prepared by a template approach. Their excellent properties as a cathode material in a lithium secondary battery of S-sequestration of elemental sulfur in the carbon capsules, a restricted polysulfide shuttling and an improved electron transport on sulfur are attributed.

This work was supported by Award No. KUS-C1-018-02, made by King Abdullah University of Science and Technology (KAUST). Facilities available through the Cornell Center for Materials Research (CCMR), a Materials Research Science and Engineering Center of the National Science Foundation (DMR-0079992) were used for this study.

We demonstrate the self-assembly through fluorophilic interactions of a blend of perfluorocarbon (RF) end-functionalized polystyrene and the corresponding RF-polybutylmethacrylate into optically transparent materials that retain domain characteristics typical of the component polymers but show well-defined lamellar nanostructured morphologies that qualitatively resemble that of the corresponding block copolymers.

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Transition metal oxides are actively investigated as anode materials for lithium-ion batteries (LIBs), and their nanocomposites with carbon frequently show better performance in galvanostatic cycling studies, compared to the pristine metal oxide. An in situ, scalable method for creating a variety of transition metal oxide–carbon nanocomposites has been developed based on free-radical polymerization and cross-linking of poly(acrylonitrile) in the presence of the metal oxide precursor containing vinyl groups. The approach yields a cross-linked polymer network, which uniformly incorporates nanometre-sized transition metal oxide particles. Thermal treatment of the organic–inorganic hybrid material produces nearly monodisperse metal oxide nanoparticles uniformly embedded in a porous carbon matrix. Cyclic voltammetry and galvanostatic cycling electrochemical measurements in a lithium half-cell are used to evaluate the electrochemical properties of a Fe3O4–carbon composite created using this approach. These measurements reveal that when used as the anode in a lithium battery, the material exhibits stable cycling performance at both low and high current densities. We further show that the polymer/nanoparticle copolymerization approach can be readily adapted to synthesize metal oxide/carbon nanocomposites based on different particle chemistries for applications in both the anode and cathode of LIBs.