Gary W. Beall

Bio: Gary W. Beall is an academic researcher from Texas State University. The author has contributed to research in topics: Monomer & Graphene. The author has an hindex of 43, co-authored 147 publications receiving 5683 citations. Previous affiliations of Gary W. Beall include Oak Ridge National Laboratory & Business International Corporation.

Polymer-clay nanocomposites

Abstract: Contributors. Series Preface. Preface. Polymer-clay Intercalates. Layered Silicate-Polymer Intercalation Compounds. Electroactive Polymers Intercalated in Clays and Related Solids. Polymer-Clay Nanocomposites Derived from Polymer-Silicate Gels. Polymerization of Organic Monomers and Biomolecules on Hectorite. Nanocomposite Synthesis and Properties. Polymer-Clay Nanocomposites. In Situ Polymerization Route to Nylon 6-Clay Nanocomposites. Epoxy-Clay Nanocomposites. Polypropylene-Clay Nanocomposites. Polyethylene Terephthalate-Clay Nanocomposites. Special Properties and Applications. Polymer-Layered Silicate Nanocomposites with Conventional Flame Retardants. Nanocomposite Technology for Enhancing the Gas Barrier of Polyethylene Terephthalate. Structure and Rheology. Structural Characterization of Polymer-Layered Silicate Nanocomposites. New Conceptual Model for Interpreting Nanocomposite Behavior. Modeling the Phase Behavior of Polymer-Clay Nanocomposites. Rheological Properties of Polymer-Layered Silicate Nanocomposites. Index.

Intercalates and exfoliates formed with oligomers and polymers and composite materials containing same

Abstract: Nanocomposites are manufactured by combining a host material, such as an organic solvent or a matrix polymer and exfoliated intercalates formed by contacting a phyllosilicate with a polymer to adsorb or intercalate the polymer between adjacent phyllosilicate platelets. Sufficient polymer is adsorbed between adjacent phyllosilicate platelets to expand the adjacent platelets to a spacing of at least about 5 A, preferably at least about 10 A (as measured after water removal), up to about 100 A and preferably in the range of about 30-40 A, so that the intercalate easily can be exfoliated, e.g., when mixed with an organic solvent or a polymer melt, to provide a carrier material for drugs and the like, or to provide a matrix polymer/platelet composite (nanocomposite) material - the platelets being exfoliated from the intercalate.

Raman spectra of the rare earth orthophosphates

Abstract: Raman spectra of anhydrous crystalline samples of all of the lanthanide orthophosphates (with the exception of PmP04) have been obtained. These data were interpreted in a systematic manner based on the known structures of these compounds. Assignments and correlations have been made for many of the observed bands. Accordingly, a series of investigations of the chemical and physical properties of the lanthanide (and related) orthophosphates is currently in progress. Single crystals of all of the lanthanide orthophosphates (except PmP0,) doped with small amounts of Gd3+ were prepared for the initial purpose of performing a series of electron paramagnetic resonance experiments. The availability of these samples made it possible to carry out a study of the Raman spectra for essentially the entire series of rare-earth orthophosphates. This study was directed toward the following objectives. First, baseline spectra were to be established that could be used as a basis of comparison with subsequent lanthanide orthophosphate crystals that would be doped with @-active actinides and, consequently, would be subjected to heavy-particle radiation damage. Second, a classification and correlation of the Raman spectra of the entire group of rare earth orthophosphates was desired. Yttrium orthophosphate was included in the present investigation because its properties are known to correlate well with those of the orthophosphates of the second half of the rare-earth series (i.e. TbP04 through LuP04) and also because YP04 is the analog of the natural mineral xenotime. In addition, a consider- able literature exists on the properties of YP04 that can be used for the purposes of verification and comparison with the lanthanide compounds. The lanthanide orthophosphates can be conveniently divided into two groups on the basis of the prevalent crystal structural form. The first group has the mono- clinic 'monazite' structure and consists of LaP04 through GdP04. The second group has the zircon struc- ture and consists of TbP04 through LuP04. Both YP04 and ScP04 also crystallize with the zircon structure and can be grouped with the orthophosphates formed by EXPERIMENTAL ~~~~ ~ ~

Review article: Polymer-matrix Nanocomposites, Processing, Manufacturing, and Application: An Overview

Abstract: This review is designed to be a comprehensive source for polymer nanocomposite research, including fundamental structure/property relationships, manufacturing techniques, and applications of polymer nanocomposite materials. In addition to presenting the scientific framework for the advances in polymer nanocomposite research, this review focuses on the scientific principles and mechanisms in relation to the methods of processing and manufacturing with a discussion on commercial applications and health/safety concerns (a critical issue for production and scale-up). Hence, this review offers a comprehensive discussion on technology, modeling, characterization, processing, manufacturing, applications, and health/safety concerns for polymer nanocomposites.

Applications of nanotechnology in food packaging and food safety: Barrier materials, antimicrobials and sensors

Abstract: In this article, several applications of nanomaterials in food packaging and food safety are reviewed, including: polymer/clay nanocomposites as high barrier packaging materials, silver nanoparticles as potent antimicrobial agents, and nanosensors and nanomaterial-based assays for the detection of food-relevant analytes (gasses, small organic molecules and food-borne pathogens). In addition to covering the technical aspects of these topics, the current commercial status and understanding of health implications of these technologies are also discussed. These applications were chosen because they do not involve direct addition of nanoparticles to consumed foods, and thus are more likely to be marketed to the public in the short term.