Nanotechnology

Researchers from University of Oklahoma describe findings in composite materials

  2008 NOV 24 - (VerticalNews.com) -- "Dispersion of nanoclay clusters during resin transfer molding of nanoclay/glass/epoxy disks is investigated. In addition to a center-gated disk containing only 14% glass fibers, three nanocomposite disks are fabricated with the addition of 2, 5 or 10 wt% Cloisite(R) 25A nanoclay," investigators in the United States report.

  "The spatial distribution of nanoclay clusters along the radial axis of the nanocomposite disks are characterized at two length scales. Clusters larger than 1.5 mu m are characterized by performing image analysis on the SEM micrographs whereas smaller nanoclay clusters are identified by wavelength dispersive spectrometry. Results obtained from image analysis indicate that nanoclay clusters are filtered out by as much as 50% in the flow direction by the glass fiber preforms. In addition, increasing nanoclay content led to higher filtration, suggesting that cluster formation is more prominent at higher nanoclay loadings. Cluster size distribution analyses revealed that the outer edges of the disks, on average, contain finer nanoclay particles. For instance, the outer edge of the nanocomposite with 2% clay contains 22% more small nanoclay clusters compared to center of the disk. Glass transition temperature, T-g, of four specimens obtained from each molded disks is characterized under oscillatory shear. Glass transition temperature of the samples are shown to increase with the nanoclay content, yielding a 40% higher Tg at 10% nanoclay loading compared to glass/epoxy composite without clay," wrote L. Aktas and colleagues, University of Oklahoma.

  The researchers concluded: "Increasing glass transition temperature with increasing nanoclay content may be an indication of intercalation of nanoclay within the epoxy matrix."

  Aktas and colleagues published their study in the Journal of Composite Materials (Filtration and breakdown of clay clusters during resin transfer molding of nanoclay/glass/epoxy composites. Journal of Composite Materials, 2008;42(21):2209-2229).

  For additional information, contact M.C. Altan, University of Oklahoma, School Aerosp & Mech Engineering, Norman, OK 73019, USA.

  The publisher of the Journal of Composite Materials can be contacted at: Sage Publications Ltd., 1 Olivers Yard, 55 City Road, London EC1Y 1SP, England.

  Keywords: Emerging Technologies, Nanoclay, Nanocomposite, Nanotech, NanotechnologyComposite Materials, University of Oklahoma.

  This article was prepared by VerticalNews Nanotechnology editors from staff and other reports. Copyright 2008, VerticalNews Nanotechnology via VerticalNews.com.