Dispersion nanocomposite morphology

Transmission electron spectroscopy (TEM) studies of the co-deposited thin films revealed a continuos polymer phase with a largely inter-dispersed SiOj regions on a 5-50 nm scale, confirming the nanocomposite morphology. As mentioned in section 3.1.3, parylene thin films obtained are typically highly crystalline. In contrast, SiO is an amorphous material. From X-ray diffraction analyses, it was observed that by increasing the relative amount of polymer in the nanocomposite, the crystallinity was... 

Recently, Tiwari and Paul (2011 a) carried out detailed studies on the effect of PP viscosity on the dispersed phase particle size, stability of dispersed phase morphology upon annealing, phase inversion behavior, and changes in the mechanical properties of PP/PP-g-MA/MMT/PS nanocomposites prepared with different molecular weight grades of PP. PP-g-MA was added to PP to facilitate dispersion of organoclay in the nonpolar PP moreover, it also provides better reinforcement effect when PP forms the continuous phase. 

Fig. 17.29 Schematic representation of the PPS/PA66 (60/40 w/w)/MWCNT nanocomposites morphology changing (a) low load MWCNTs (<0.5 phr) disperse evenly and form a percolating network, and (b) high load MWCNTs (>0.5 phr) aggregate like clews (Zou et al. 2006)...

The dispersion and morphology of the P3HT-MWNT nanocomposites can be examined through transmission electron microscopic (TEM) images (Figure 12.3) [50]. The nanotubes are in the outer diameter range of 8 to 40 nm with mostly... 

The method used to disperse clay into the monomer is important as good dispersion in the monomer is vital for the final nanocomposite morphology. Although the surface modification of the clay is a critical aspect in determining the compatibility between the styrene and the clay, the method used to disperse the day is also important, and in most cases some form of mechanical stirring is used as a minimum. Other methods can improve the ability to exfoliate including ultrasonic [87, 101] and direct electric current [102]. 

The two basic tools used to elucidate nanocomposite morphology are x-ray diffraction (xrd) and transmission electron microscopy (tern). They provide complementary information on clay dispersion in the host matrix. 

This chapter surveys the strong influence of the quality of dispersion, structure, morphology, and aspect ratio on the properties of PI nanocomposites containing various nanoparticles with different shapes and sizes. X-ray diflEraction and TGA measurements confirm that... 

The use of a commercial Cloisite 20A organoclay to prepare SBS-based nanocomposites by melt processing was recently reported [63]. In this case, the nanocomposite morphology was characterized by a combination of intercalated and partly exfoliated clay platelets, with occasional clay aggregates present at higher clay content. For this particular thermoplastic elastomer nanocomposite system, well-dispersed nanoclays lead to enhanced stiffness and ductility, suggesting promising improvements in nanocomposite creep performance. The use of stearic acid as a surface modifier of montmorillonite clay to effectively improve the clay dispersion in the SBS matrix and the mechanical properties of the SBS-clay nanocomposites was reported [64]. 

Elastomer nanocomposites with one-dimensional nanofillers have been presented in this chapter. The nature of nanofiller has been altered from nanotube to nanorod, and nanofiber with their suitable chemical modifications required for the improvement of various properties. The dispersion and morphology have been explored for... 

Unlike melt intercalation, a layered silicate is mixed with monomer before polymerization takes place with in situ polymerization. This method was developed by Toyota researchers [27,28], in which electrostatically held 1-nm thick layers of layered alumina silicates were dispersed in a polyamide matrix on a nanometer level, which led to an exponential growth in the research endeavors, in layered silicate nanocomposites. These nanocomposites were based on the in situ synthesis approach in which a monomer or monomer solution was used to swell the filler interlayers, followed by polymerization. With this process, one can control the nanocomposite morphology through the combination of reaction conditions and clay surface modification. The in situ polymerization method is especially important for insoluble and thermally unstable polymers, which solution blending or melt blending technique cannot process. 

Therefore, this objective of this study was to evaluate the influence of compounding route of PVC/clay nanocomposites on their flexural, tensile, dispersion, and morphology properties. Particular emphasis was placed on following the fusion curves during blend mixing in order to develop novel strategies of introducing nanoclay into PVC matrix. 

Noble metal nanoparticles dispersed in insulating matrices have attracted the interest of many researchers fromboth applied and theoretical points of view [34]. The incorporation of metallic nanoparticles into easily processable polymer matrices offers a pathway for better exploitation of their characteristic optical, electronic and catalytic properties. On the other hand, the host polymers can influence the growth and spatial arrangement of the nanoparticles during the in situ synthesis, which makes them convenient templates for the preparation of nanoparticles of different morphologies. Furthermore, by selecting the polymer with certain favorable properties such as biocompatibiHty [35], conductivity [36] or photoluminescence [37], it is possible to obtain the nanocomposite materials for various technological purposes. 

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