Preparation of Polymer Nanocomposites

In the previous several years, various nanoparticles have been assembled into pairs to fabricate polymer nanocomposites, such as clay/silica (45), clay/carbon black (43), CNTs/clay (41,42), and CNTs/Titanium (38). Polymer/CNTs/clay ternary composite is one of most important multiphase systems with interesting synergistic effect, where sodium based montmorillonite (MMT) are the most commonly used layered clay. In this chapter, we will select some typical examples to demonstrate the importance and synergies of using CNTs and clay together in the preparation of polymer nanocomposites. 

The properties of polymer nanocomposites are influenced by numerous factors including nanofillers type, purity, and the match between clay and CNT dimensions (length and diameter). These factors should be taken into account in the preparation of polymer nanocomposite, as well as in process of reporting and interpreting the experimental data. 

Graphene-polymer nanocomposites share with other nanocomposites the characteristic of remarkable improvements in properties and percolation thresholds at very low filler contents. Although the majority of research has focused on polymer nanocomposites based on layered materials of natural origin, such as an MMT type of layered silicate compounds or synthetic clay (layered double hydroxide), the electrical and thermal conductivity of clay minerals are quite poor [177]. To overcome these shortcomings, carbon-based nanofillers, such as CB, carbon nanotubes, carbon nanofibers, and graphite have been introduced to the preparation of polymer nanocomposites. Among these, carbon nanotubes have proven to be very effective as conductive fillers. An important drawback of them as nanofillers is their high production costs, which... 

Z. Lei and S. Bi, Preparation of polymer nanocomposites of core-shell structure via surface-initiated atom transfer radical polymerizations. Mater. Lett., 61, 3531-3534 (2007). 

Weibel, M., Caseri, W., Suter, U. W., Kiess, H., and Wehrli, E., Preparation of polymer nanocomposites with ultrahigh refractive index, Polym. Adv. Tech., 2, 75-80 (1991). 

Preparation of polymer nanocomposites is nowadays an important research subject since polymer properties can be enhanced (e.g., modulus, strength, thermal resistance, per-meabifity, flammabifity resistance, and even biodegradability)... 

During the past decades, nanotechnology has attracted great attention due to its marvellous potential applications in numerous areas [90]. Polymer nanocomposite is a unique addition in the nanotechnology family. In polymer nanocomposite, one phase is dispersed in another phase in nanometer level [19]. Different types of reinforcing fillers such as sodium montmo-rillonite, sodium bentonite, layered double hydroxide, exfohated graphite, fullerene, carbon nanofiber, and carbon nanotube have been successfully used in the preparation of polymer nanocomposites [19]. Recently,... 

To obtain a homogeneous and thermodynamically stable dispersion of nanomaterials in the polymer matrix, a variety of techniques are used in vegetable oil-based polymer nanocomposites. The state of dispersion of nanomaterials in the polymer matrix is the main governing factor in obtaining the required nanocomposites. However, depending on the suitability, end-use applications and cost, the three most widely used methods for the preparation of polymer nanocomposites are (i) the solution technique, (ii) in situ polymerisation and (hi) the melt mixing technique. ... 

Cas-Phase-Assisted Surface Polymerization and Thereby Preparation of Polymer Nanocomposites... 

Around 1900, widely forgotten reports indicated the preparation of polymer nanocomposites with uniaxially oriented inorganic particles, and their remarkable optical properties (14,15). Dichroic plants and animal fibrils (eg, linen, cotton, spruce, or chitin, amongst others) were prepared by impregnation with solutions of silver nitrate, silver acetate, or gold chloride, followed by reduction of the corresponding metal ions under the action of light (16). 

One of the most important steps in the preparation of polymer nanocomposites is the mixing process. In order for the properties of a compatible nanostructured reinforcement to be fully exploited, it has to be well distributed and well dispersed. 

It is well-known that montmorillonite (MMT) clay is the most used clay in polymer/ clay nanocomposite foams. Hence, it is suitable to present the effect of adding montmorillonite clay in the preparation of polymer nanocomposite foams and its effect... 

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