Polymer/graphite nanocomposites structures

Transmission electron microscopy (TEM) is also widely employed, in its simplest bright-field mode, as a tool for direct visualization of the nanocomposite structure of polymer nanocomposites. This is possible because there exists sufficient contrast for the transmitted electrons between the polymer matrix and most fillers (inorganic particles, carbon in nanotubes or graphite, and almost all oxides) without polymer staining. In the extreme case, high-resolution TEM can even provide a qualitative picture of the inorganic filler crystal structure, or can be... 

Causin, V., Marega, C Marigo, A., Ferrara, G., and Ferraro, A. (2006) Morphological and structural characterization of polypropylene/conductive graphite nanocomposites. European Polymer Journal, 42, 3153-3161. 

It is necessary to disperse the nanomaterials in the best possible manner, especially those layered structures such as graphite, graphene or clays. It is important to obtain very thin (ca. one nanometer) and very wide (ca. 500 nanometers) nanostructures dispersed in the polymer matrices to achieve optimal gas permeability and to improve their mechanical properties without affecting structural quality, using a small amount of the nanomaterial. The particle orientation also has an important effect on the properties of the nanocomposite. Nanoparticles need to be dispersed within the polymer so that are parallel to the material s surface. This condition ensures a maximum tor-... 

Carbon materials provide electrical conduction through the pi bonding system that exists between adjacent carbon atoms in the graphite structure [182]. Electrical properties of nanocomposites based on conducting nanofillers such as EG [183-187], CNTs [188-190], and CNFs [191], dispersed in insulating polymer matrix have found widespread applications in industrial sectors. 

Most of the previous studies on flame retardation of polymer nanocomposites are focused on the relationship between macroscopic morphologies of chars and the flammability properties. Fang et al. studied the relationship between evolution of the microstructure, viscoelasticity and graphitization degree of chars and the flammability of polymers during combustion (68). The flame retar-dancy of ABS/clay /MWNTs nanocomposites was strongly affected by the formation of a network structure. Flammability properties... 

The main reason for the recent popularity of nanotechnology is that the reduction of the dimensions of a material to nanosize leads to new specific properties [82]. It is crucial to understand the intrinsic mechanical properties of CNFs in order to incorporate them into polymer resins to fabricate CNFs-reinforced nanocomposites. Because of the structural complexity of CNFs derived from variations in inner and outer wall thickness, cone angle, orientation of graphite plane, and C-C bonds, determination of their mechanical properties had posted considerable difficulties. To date, direct measurement of tensile properties of CNFs is accessible only with the aid... 

The art of filler dispersion in polymer matrix is easily determined by X-ray analysis especially WAXS analysis. The intensity and position of X-ray diffraction peaks reveals the exact idea regarding the morphological structure of polymer nanocomposites. Figure 22.11 compares reduced graphite oxide dispersions in NR matrix by different processes such as milling and solution casting methods. 

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