Polymer nanocomposites generalities

In situ polymerization is generally a highly suitable method for the ob-tention of LDH/polymer nanocomposites. Various monomers can be intercalated and polymerized within the interlamellar space of LDH and this spatial confinement is believed to increase the degree of polymerization. Yet, the process is limited by two factors [43] ... 

The general procedures so far used for obtaining clay-polymer nanocomposites may be classified as below. 

It is generally accepted that thermal stability of polymer nanocomposites is higher than that of pristine polymers, and that this gain is explained by the presence of anisotropic clay layers hindering diffusion of volatile products through the nanocomposite material. It is important to note that the exfoliated nanocomposites, prepared and investigated in this work, had much lower gas permeability in comparison with that of pristine unfilled PE [12], Thus, the study of purely thermal degradation process of PE nanocomposite seemed to be of interest in terms of estimation of the nanoclay barrier effects on thermal stability of polyolefin/clay nanocomposites. 

Generally, polymer nanocomposites can be obtained through two routes the first one is the polymerization of monomers in contact with the exfoliated clay and the second one uses existing transformation processes to produce nanocomposites, for example, by a reactive extrusion. There are, however, problems present due to the lack of affinity of the clay-polymer system because of the hydrophilic character of the particles. It is then necessary to treat the clay chemically to increase its affinity with the polymer matrix. This constitutes another whole area of research in the nanocomposites production. 

Polymer nanocomposites multicomponentness (multiphaseness) requires their stmctural components to be quantitative characteristics determination. In this aspect, interfacial regions play a particular role, as it has been shown earlier, that they are the same reinforcing element in elastomeric nanocomposites as nanofiller actually [ 1 ]. Therefore, the knowledge of interfacial layer dimensional characteristics is necessary for quantitative determination of one of the most important parameters of polymer composites, in general,— their reinforcement degree [2, 3]. 

Polymer nanocomposites are generally prepared by three methods solution intercalation, in-situ polymerisation or melt compounding. 

This is a very common method for the preparation of graphene/conjugated polymer nanocomposites. In a typical synthetic procedure, surface-modified graphene or GO can be dispersed in acidic water and /or surfactant solution followed by the addition of monomer. It was then stirred obeying a certain conditions to disperse filler in the solvent and monomer homogeneously. Finally, the initiator (generally peroxides are used as initiator) is added to initiate the polymerization reaction at a certain temperature. Aniline, pyrrole, thiophene, 3,4-ethylenedioxythiophene, etc. can be polymerized by this method [73-80]. 

General Methods for Preparation of Conjugated Polymer Nanocomposite... 

For poor solubility as well as poor film forming nature of the rigid conjugated polymer and its nanocomposites, generally pellet is used as... 

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