Bio-nanocomposites for food packaging applications

This article reports on the International Nanofluid Property Benchmark Exercise, or INPBE, in which the thermal conductivity of identical samples of colloidally stable dispersions of nanoparticles or “nanofluids,” was measured by over 30 organizations worldwide, using a variety of experimental approaches, including the transient hot wire method, steady-state methods, and optical methods. The nanofluids tested in the exercise were comprised of aqueous and nonaqueous basefluids, metal and metal oxide particles, near-spherical and elongated particles, at low and high particle concentrations. The data analysis reveals that the data from most organizations lie within a relatively narrow band (±10% or less) about the sample average with only few outliers. The thermal conductivity of the nanofluids was found to increase with particle concentration and aspect ratio, as expected from classical theory. There are (small) systematic differences in the absolute values of the nanofluid thermal conductivity among the various experimental approaches; however, such differences tend to disappear when the data are normalized to the measured thermal conductivity of the basefluid. The effective medium theory developed for dispersed particles by Maxwell in 1881 and recently generalized by Nan et al. [J. Appl. Phys. 81, 6692 (1997)], was found to be in good agreement with the experimental data, suggesting that no anomalous enhancement of thermal conductivity was achieved in the nanofluids tested in this exercise.

A Benchmark Study on the Thermal Conductivity of Nanofluids

The addition of inorganic spherical nanoparticles to polymers allows the modification of the polymers physical properties as well as the implementation of new features in the polymer matrix. This review article covers considerations on special features of inorganic nanoparticles, the most important synthesis methods for ceramic nanoparticles and nanocomposites, nanoparticle surface modification, and composite formation, including drawbacks. Classical nanocomposite properties, as thermomechanical, dielectric, conductive, magnetic, as well as optical properties, will be summarized. Finally, typical existing and potential applications will be shown with the focus on new and innovative applications, like in energy storage systems.

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Polymer-Nanoparticle Composites: From Synthesis to Modern Applications

Starch-based nano-biocomposites

Polymer nanocomposites from modified clays: Recent advances and challenges

The mechanics of nanocomposites is critical in the design of nanomaterials with desirable properties In this paper, the mechanics of polymer−clay nanocomposites is studied using a designed polymer and solution nanocomposite synthesis A copolymer latex, with function groups that strongly interact with the surface of the clay nanoplatelet and glass-transition temperature lower than room temperature, was synthesized Uniformly dispersed nanocomposites were then generated using water as the intercalation agent through the solution process The chain mobility in the nanocomposites is greatly reduced as studied by dynamic mechanical thermal analysis (DMTA) and dielectric thermal analysis (DETA) The modulus of the composite increases significantly The modulus enhancement strongly relates to the volume of the added clay as well as the volume of the constrained polymer This modulus enhancement follows a power law with the content of the clay and is modeled well by Mooney's equation for this soft-polymer-based

Mechanics of Polymer−Clay Nanocomposites

Structure–property relation in poly(p-phenylene terephthalamide) (PPTA) fibers

Gelatin–clay nanocomposites of improved properties ☆

Nanofluids:Stability, phase diagram, rheology and applications

Little data exist on how twist changes the properties of high-performance continuous fiber yarns. For this reason, a study was conducted to determine the influence of twist on the strength and stiffness of a variety of high-performance continuous polymeric fiber yarns. The materials investigated include Kevlar 29®, Kevlar 49®, Kevlar 149®, Vectran HS®, Spectra 900®, and Technora®. Mechanical property tests demonstrated that the initial modulus of a yarn monotonically decreases with increasing twist. A model based on composite theory was developed to elucidate the decrease in the modulus as a function of both the degree of twist and the elastic constants of the fibers. The modulus values predicted by the model have good agreement with those measured by experiment. The radial shear modulus of the fiber, which is difficult to measure, can be derived from the regression parameter of experimental data by the use of the model. Such information should be useful for some specialized applications of fibers, for example, fiber-reinforced composites. The experimental results show that the strength of these yarns can be improved by a slight twist. A high degree of twist damages the fibers and reduces the tensile strength of the yarn. The elongation to break of the yarns monotonically increases with the degree of twist. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 1938–1949, 2000

YuanQiao Rao

Papers

Mechanics of Polymer−Clay Nanocomposites

Structure–property relation in poly(p-phenylene terephthalamide) (PPTA) fibers

Gelatin–clay nanocomposites of improved properties ☆

Nanofluids:Stability, phase diagram, rheology and applications

A modeling and experimental study of the influence of twist on the mechanical properties of high‐performance fiber yarns