Nanofiller composites characterization

Ghose, S., Watson, K.A., EUiott, H.A., Working, D.C., Criss, JM., Dudley, K.L., Connell, J.W., 2006. Fabrication and characterization of high temperature resin/carbon Nanofiller composites. In ASME 2006 Multifunctional Nanocomposites International Conference, pp. 69-77. 

The calculated dimensions D, based on the aforementioned method, are adduced in Table 6.2. The values for the studied nanocomposites are varied within the range of 1.10-1.36, i.e., they characterize more or less branched linear formations ( chains ) of nanofiller particles (aggregates of particles) in elastomeric nanocomposite structure. Let us remind that for particulate-filled composites polyhydroxyether/graphite, the value changes within the range of 2.30-2.80 [4, 10], i.e., for these materials filler particles network is a bulk object, but not a linear one [36]. 

Up to now we considered pol5meric fiiactals behavior in Euclidean spaces only (for the most often realized in practice case fractals structure formation can occur in fractal spaces as well (fractal lattices in case of computer simulation), that influences essentially on polymeric fractals dimension value. This problem represents not only purely theoretical interest, but gives important practical applications. So, in case of polymer composites it has been shown [45] that particles (aggregates of particles) of filler form bulk network, having fractal dimension, changing within the wide enough limits. In its turn, this network defines composite polymer matrix structure, characterized by its fractal dimension polymer material properties. And on the contrary, the absence in particulate-filled polymer nanocomposites of such network results in polymer matrix structure invariability at nanofiller contents variation and its fractal dimension remains constant and equal to this parameter for matrix polymer [46]. 

This chapter reviews the use of the sepiolite/palygorskite group of clays as a nanofiller for polymer nanocomposites. Sepiolite and palygorskite are characterized by a needle-like or fiber-like shape. This peculiar shape offers unique advantages in terms of mechanical reinforcement while, at the same time, it allows to study the effect of the nanofiller s shape on the final composite properties. The importance of the nanofiller shape for the composite properties is analyzed in Section 12.2, introducing the rationale of the whole chapter. After a general description of needle-like nanoclays in Section 12.3, the chapter develops into a main part (Section 12.4), reviewing the preparation methods and physical properties of polyolefin/needle-like clay nanocomposites. 

This book focuses on the synthesis and characterization of natural rubber composites and nanocomposites, the interaction between reinforcing agents and the rubber matrix and their effect on different properties. The reinforcing effect of traditional fillers in micro range and the effectiveness of these nanofillers are discussed. This book on natural rubber and nano composites comprises of the most recent research activities that will, unquestionably, be a vital reference book for scientists in both the academic and industrial sectors, as well as for individuals who are interested in natural rubber materials. 

For the comprehension of mechanisms involved in the appearance of novel properties in polymer-embedded metal nanostructures, their characterization represents the fundamental starting point. The microstructural characterization of nanofillers and nanocomposite materials is performed mainly by transmission electron microscopy (TEM), large-angle X-ray diffraction (XRD), and optical spectroscopy (UV-vis). These three techniques are very effective to determine particle morphology, crystal structure, composition, and grain size (48). 

In addition to morphological characterization, analysis techniques such as FTIR and NMR were also reported to be employed in the structural characterization of the nanocomposites. For example, the ester carbonyl group of neat PHA usually shows a vibration at 1724-1731 cm . In a nanocomposite, this peak is normally moved to a lower wavelength below 1724 cm (Figure 5.10), probably due to reported hydrogen bond formation with the composite nanofiller. ... 

In this chapter, a review of several researches done on the development and characterization of nanocomposites based on starch will be presented. Special attention will be given to the influences of the incorporation of starch, cellulose, layered silicate, and antioxidant and/or antimicrobial nanofillers on the physicochemical properties of the composites. The discussion will be focused on structural, mechanical, and barrel properties as well as on degradation, antibacterial and antioxidant activities. 

Recentiy, a new class of organic-inorganic hybrid materials based on the ultra incorporation of nano-sized fillers (nanofillers) into a polymer matrix has been investigated. Nanotechnology is the aptitude to work on a scale of about 1-100 nm in order to understand, create, characterize and use material structure, devices, and system with unique properties derived from their base on the nanostructures. Nanocomposites could exhibit exclusive modifications in their properties, compared with conventional composites in terms of physical properties, including gas barrier, flammability resistance, thermal and environmental stability, solvent uptake, and rate of biodegradability of biodegradable (Chivrac et al. 2009). 

Nanocomposites are a relatively new class of hybrid materials characterized by an ultra fine dispersion of nanofillers into a polymeric matrix. As the result of this dispersion, these materials possess unique properties, behaving much diflferentiy than conventional composites or microcomposites, and offering new technological and economical opportunities. The first studies on nanocomposites were carried out in 1961, when Blumstein performed the polymerization of vinyl monomer intercalated into montmorillonite structure. Since then, clay-based polymer nanocomposites have emerged as a new class of materials and attracted considerable interest and investment in research and development worldwide (Schaefer and Justice 2007). 

The majority of the research work recently published in the area of carbon nanofillers focuses on the characterization of polymer composites with functionalized-graphene sheets, as indicated in a bibliometric survey conducted by Peng et al. (Lv et al., 2011). However, some studies are available in which the characterization of mechanical and functional properties of polymer—intercalated/exfoliated graphite oxide or GO is reported, as summarized in the following sections. 

The chapter deals with a brief account of various topics in polyethylene-based blends, composites and nanocomposites. We discuss the different topics such as ultra high molecular weight polyethylene (UHMWPE) for orthopaedics devices, stabilization of irradiated polyethylene by the introduction of antioxidants, polyethylene-based conducting polymer blends and composites, polyethylene composites with hgnocellulosic material, LDH as nanofillers of nanocomposite materials based on polyethylene, ultra high molecular weight polyethylene and its reinforcement/oxidative stability with carbon nanotubes in medical devices, montmorillonite polyethylene nanocomposites, and characterization methods for polyethylene based composites and nanocomposites. 

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