Magnetic polymer nanocomposites component

Nowadays a promising way to control the bulk polymer properties, such as conductivity, processability, thermal, and mechanical stabihties, is through the organization of the polymeric chains on the nanometer scale [7-9]. The first approach used to achieve this goal was the synthesis of conducting polymers in cavities of porous hosts. Commonly named nanocomposites, these materials have two or more different components on the nanoscale, and can show catalytic, electronic, magnetic, and optical properties better than those of the individual phases. The basic reason for this synergism is still not fully understood, but it is considered that confinement and electrostatic interactions between the components play an important role. 

According to the matrix, nanocomposites may be classified into three categories i) Ceramic matrix nanocomposite, ii) metal matrix nanocomposites, and iii) polymer matrix nanocomposite. In the first group of composites the matrix is a ceramic material, i.e., a chemical compoxmd from the group of oxides, nitrides, borides, silicides, etc. In most cases of ceramic-matrix nanocomposites the dispersed phase is a metal, and ideally both components, the metallic one and the ceramic one, are finely dispersed in each other in order to elicit the particular nanoscopic properties. Nanocomposites from these combinations were demonstrated to improve their optical, electrical and magnetic properties [5,4], as well as tribological, corrosion-resistance and other protective properties [6,5]. Thus the safest measure is to carefully choose immiscible metal and... 

The polymer performance and production efficiency can be enhanced as a function of the basic features of the reinforcement fillers. In the attempt to achieve fillers with increased performance, the following features must be monitored density, flame retardancy, mechanical resistance, thermal conductivity, and magnetic properties. Nanoparticles of carbides, nitrides, and carbonitrides can be used to reinforce polymer matrix nanocomposites with desirable thermal conductivity. However, current trends in the design of these materials reveal that is not enough to choose a wellperforming material for each component of the heat dissipation path. In addition, careful attention must be paid to the manner in which these materials interact with each other. A filler that conducts heat well but does not wet the matrix may lead to poor results compared to a lower conductivity filler that does wet the matrix. In other words, a major fact that leads to interfacial resistance is faulty physical contact between filler and matrix, which primarily depends on surface wettability (Han and Fina2011). 

In brief, the preparation methods of these nanocomposites can be classified in four main routes proposed in the literature that are graphically represented in Fig. 2 for the preparation of composites based on PPy. In the first strategy, both components, the polymer and the magnetic nanoparticles are synthesized separately and then mixed to produce the nanocomposite. This route presents as the main inconveniences that the conducting polymers, i.e., PPy, are not soluble in common solvent and also this method normally conducts to heterogeneous composites with... 

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