Transmission electron microscopy benefits

Nylon-6. Nylon-6—clay nanometer composites using montmorillonite clay intercalated with 12-aminolauric acid have been produced (37,38). When mixed with S-caprolactam and polymerized at 100°C for 30 min, a nylon clay—hybrid (NCH) was produced. Transmission electron microscopy (tern) and x-ray diffraction of the NCH confirm both the intercalation and molecular level of mixing between the two phases. The benefits of such materials over ordinary nylon-6 or nonmolecularly mixed, clay-reinforced nylon-6 include increased heat distortion temperature, elastic modulus, tensile strength, and dynamic elastic modulus throughout the —150 to 250°C temperature range. 

The interaction between an electron and a specimen is what makes X-ray analysis and electron microscopy possible, and these two analytical techniques are often used in collaboration with each other in reverse engineering. A brief review of electron specimen interaction and the subsequent emission will be discussed in this section, which will benefit the later discussion on material identification utilizing these techniques. When the energetic electrons in the microscope strike the specimen, a variety of reactions and interactions will occur, as shown in Figure 5.3. The electrons emitted from the top of the specimen are utilized to analyze the bulk samples in scanning electron microscopy (SEM), while those transmitted through the thin or foil specimens are used in transmission electron microscopy (TEM). 

FIGURE 19 (a) The corrector of Fig. 18 incorporated in a transmission electron microscope, (b) The phase contrast transfer function of the corrected microscope. Dashed line no correction. Full line corrector switched on, energy width (a measure of the temporal coherence) 0.7 eV. Dotted line energy width 0.2 eV. Chromatic aberration remains a problem, and the full benefit of the corrector is obtained only if the energy width is very narrow. [From Haider, M., et al. (1998). J. Electron Microsc. 47,395. Copyright Japanese Society of Electron Microscopy.]... 

Several review papers discuss the preparation, characterization, properties, and applications of bio-nanocomposites (Pandey et al., 2005 Ray and Bousmina, 2005 Yang et al, 2007 Rhim and Ng, 2007 Sorrentino et al., 2007 Zhao et al., 2008 Bordes et al., 2009). However, there is a lack of comprehensive review on various analytical techniques for the stmctural characterization of bio-nanocomposites. Selection of proper technique for characterization of these bio-nanocomposites is very critical in assessing their performance. A number of analytical techniques have been used to characterize the stracture of bio-nanocomposites. These techniques include X-ray diffraction (XRD), microscopy transmission electron microscope (TEM), scanning electron microscope (SEM), scanning probe microscope (SPM), and confocal scanning laser microscope (CSLM), Fourier transform infra-red (FTIR) spectroscopy, and nuclear magnetic resonance (NMR). Each of the above mentioned techniques has its own benefits and limitations. 

---