Moisture diffusion was studied through vinyl ester samples containing up to 5 wt% of organically treated montmorillonite. Two different kinds of clay surface treatment were employed to make the clay compatible with DerakaneTM 411‐350 vinyl ester resin. The nanocomposites were characterized using differential scanning calorimetry (DSC), mechanical property measurements, X‐ray diffraction (XRD) and transmission electron microscopy (TEM). TEM pictures showed that the clay platelets were either exfoliated or intercalated, and the two different surface treatments resulted in different dispersion characteristics. All the samples were post cured, and the diffusivity of moisture was measured by soaking the samples in 25°C water and noting the increase in weight with increasing time of immersion. It was found that water diffusivity decreased with increasing clay content, and it was reduced to half its value in the neat resin when the clay content was only 1 wt% regardless of the nature of clay surface treatment. However, the equilibrium moisture content, the glass transition temperature, and the elastic modulus all increased with increasing amounts of clay.

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Written for graduate students, researchers, and practitioners, Fundamentals of Polymer-Clay Nanocomposites provides a complete introduction to the science, engineering, and commercial applications of this new class of material. Starting with a discussion of general concepts, the authors define in detail the specific terms used in the field, providing newcomers with a strong foundation in the area. Then, the physical and mechanical properties of polymer-clay nanocomposites are described, with chapters on thermodynamics and kinetics, engineering properties, barrier properties, and flame retardancy. Mechanisms underpinning observed effects, such as UV resistance, solvent resistance, and hardness, are also explained. Throughout each chapter, experimental results are combined with theory, ensuring that the reader gains a full appreciation of the subject matter. In-depth discussions of clay and clay surface treatment, fabrication, and characterization of nanocomposites are provided, and particular emphasis is placed on the proper use and interpretation of analytical techniques, helping the reader to avoid artifacts in their own work. With commercial applications discussed throughout, this is an ideal reference for those working in polymer science.

Critical micelle concentrations were determined for 2-octylammonium and 2-octyltrimethylammonium ions in the presence of various counterions. The kinetics and the stereochemistry of the aqueous nitrous acid deamination of 2-aminooctane were studied under micellar and nonmicellar conditions. Micellar catalysis of the deaminative rate (about 15-fold) was observed. Some catalysis was observed, whatever the identity of the anions present during the deamination. The stereochemistry of the 2-aminooctane to 2-octanol conversion could be changed from 24 % net inversion (nonmicellar) to 6% net retention, under certain micellar deamination conditions. In contrast to the kinetic results, the stereochemical effects were highly dependent on the identity of the counterions.

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