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Kosower, Dodiuk, Kanety / N-Arylaminonaphthalenesuljonates 4179 trogen since the shape 01 the emission curves is not affected and the quantum yields of fluorescence only slightly increased in nonpolar solvents (unchanged in medium-and high-polarity solvents) by such purging. Sample temperatures were controlled a t 25.0 & 0.5 O C . Dioxane was from E. Merck, Darmstadt (spectrograde). Plots were executed with a Hewlett-Packard 98 10-9862 calculator-plotter combination.Acknowledgment. The support of the United States-Israel Binational Science Foundation (BSF) is appreciated. References and Notes(1) (a) Tel-Aviv University; (b) State University of New York, Stony Brook.(2) Previously, we numbered the Narylamino group as 2-, but we have accepted the editorial suggestion that 6is more appropriate and conforms more closely to accepted nomenclature. (IO) H. Bucherer and A. Stohmann, Chem. Zentralbl., 75, 1012 (1904); see also ref 5 and 6. (1 1) E~(30) values represent an intramolecular charge-transfer transition whereas Zvalues are based on an intermolecular charge-transfer transition. The former are therefore more suitable for the analysis of ANS emission data according to the suggestions previously made in ref 3 and 4. (24) (25)

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In this paper we evaluated the effect of embedding inorganic nanotubes (INT) of tungsten disulfide (WS 2 ) in an epoxy matrix, on the mechanical, thermal and adhesion properties of the resulting nanocomposites. The nanotube content spanned a range of values (0, 0.1, 0.3, 0.5 and 1.0 wt%), and the nanotube incorporation process consisted of a combination of both distributive (magnetic stirring) and dispersive (ultrasonic mixing) methods. The adhesion of the nanocomposites to an aluminum substrate was characterized by both a single lap shear and a T-peel test. The fracture toughness (K IC ) of the nanocomposites was characterized by a standard compact tension (CT) plane-strain fracture test. The thermal properties of the nanocomposites were determined by dynamic mechanical thermal analysis (DMTA). Overall, the addition of INT-WS 2 was found to improve the shear strength and peel properties of the nanocomposite, and to significantly improve its fracture toughness and glass transition temperature. The extent and character of the nanotube-epoxy interaction were examined by electron microscopy, as was the energy dissipation mechanisms during fracture.

The effects of nano and micro roughness as well as the chemical composition of surface treatments on hydrophobicity and self‐cleaning properties of the coated surfaces were studied theoretically and experimentally. Accordingly, relationships were derived between the interfacial adhesion strength of the liquid drop to a polymer surface of a given composition, the mass of the drop, the measured contact angles, and the sliding angle. To verify the proposed model various hydrophobic coatings having different surface nano and micro roughness were prepared using polycarbonate (PC) as a substrate. The surface treatment was based on fluoroalkylsilane. Roughness was introduced by means of Silica (micro) and polyhedral oligomeric silsesquioxane (POSS; nano) using a double morphology topography mimicking the Lotus leaf. In the case of optimal compositions and processing conditions, transparent ultra‐hydrophobic characteristics were obtained. In these cases the contact angle was close to 180° and the sliding angle was below 5°. These novel ultra‐hydrophobic surface coatings and the associated model could be used to develop and design surfaces for a variety of applications such as self‐cleaning glazing, repellent surfaces for threats from biochemicals, and anti‐icing of surfaces. Copyright © 2007 John Wiley & Sons, Ltd.