Polymer nanocomposites nanocomposite materials applications

The goal of this chapter is to provide general information on the synthesis and characterization of various conducting polymer nanocomposite materials for energy storage device application with recent development of this new area of research. 

V. Rangari, Polymer nanocomposite materials for structural applications, in B. Reddy, ed.. Advances in Nanocomposites - Synthesis, Characterization and Industrial Applications, InTech, pp. 61-84,2011. 

The chapter demonstrates that in spite of the incompatibility between hydrophilic natural fibres and hydrophobic polymeric matrices, the properties of natural fibre composites can be enhanced through chemical modifications. The chemical treatments have therefore played a key role in the increased applications of natural fibre composites in the automotive sector. Recent work has also shown that if some of the drawbacks of natural fibres can be adequately addressed, these materials can easily replace glass fibres in many applications. The chapter has also shown that there have been attempts to use natural fibre composites in structural applications, an area which has been hitherto the reserve of synthetic fibres like glass and aramid. The use of polymer nanocomposites in applications of natural fibre-reinforced composites, though at infancy, may provide means to address these efficiencies. Evidence-based life-cycle assessment of natural fibre-reinforced composites is required to build confidence in the green composites applications in automotive sector. 

Therefore, it appears that a combination of organoclays and conventional flame retardants possesses significant potential to be useful flame retardant systems. A more detailed understanding of the flame retardant mechanism by which such an additive combination exerts its positive effects may further improve its performance and safety and reduce overall additive loading and cost. Moreover, the development of feasible and relevant manufacturing methods based on the intercalated flame retardant clays described here which facilitate the dispersion of flame retardant additives and increase flame retardant efficiency foretells of a promising future for flame retardant polymer nanocomposite materials in everyday applications. 

This book focuses on the subject of foams generated with polymer nanocomposite materials. Polymer nanocomposites have been developed continuously for the last two decades. These advancements have led to their application in many fields such as automotive, packaging, insulation, and so forth. Foams are one product, which is common to many application fields and also has high commercial value. Use of nanocomposites in the formation of foams enhances the property profiles such as porosity control, strength, stiffness, and so on, significantly, which enables the application of such materials in conventional areas ranging to more advanced ones. 

As one of the possible applications of the present CNF film, authors have studied the surface-initiated ring-opening graft polymerization of cyclic monomers from the CNF film to prepare new CNF/synthetic polymer nanocomposite materials (Fig. 14.8]. 

Industrial Applications Carbon nanotubes (single-wall carbon nanotubes (SWCNT) and multi-wall carbon nanotubes (MWCNTs)) " " cellulose materials for bulky paper sheets graphene-based polymer nanocomposites materials/films " photonic materials photovoltaic devices polyaniline systems poly(dimethylsiloxane) (PDMS) oligomers poly(propylene imine) dendrimers " thin-films ... 

In recent several years, super-capacitors are attracting more and more attention because of their high capacitance and potential applications in electronic devices. The performance of super-capacitors with MWCNTs deposited with conducting polymers as active materials is greatly enhanced compared to electric double-layer super-capacitors with CNTs due to the Faraday effect of the conducting polymer as shown in Fig. 9.18 (Valter et al., 2002). Besides those mentioned above, polymer/ CNT nanocomposites own many potential applications (Breuer and Sundararaj, 2004) in electrochemical actuation, wave absorption, electronic packaging, selfregulating heater, and PTC resistors, etc. The conductivity results for polymer/CNT composites are summarized in Table 9.1 (Biercuk et al., 2002). 

Abstract This chapter is intended to provide a state-of-the-art review of nanocomposite materials prepared by the assembly of layered double hydroxides (LDH) and polymers, including their synthesis and characterization, and point out their potential applications. 

Fischer, H. (2003). Polymer nanocomposites from fundamental research to specific applications. Materials Science and Engineering C, 23, 763-772. 

CNT nanocomposites morphological and structural analysis is often done by TEM but an extensive imaging is required then to ensure a representative view of the material. Moreover, carbon based fillers have very low TEM contrast when embedded in a polymer matrix. The application of microscopy techniques is very useful to control the status of CNTs at any time during the preparation process of CNT/polymer nanocomposites, and moreover, to gain insights on parameters important for a better understanding the performance of the final nanocomposite material based on CNTs. 

As mentioned earlier, polymerization techniques can also be used in the presence of nanotubes for preparation of polymer/CNT nanocomposite materials. In these, in-situ radical polymerization techniques of polymerization in the presence of CNT filler under or without applied ultrasound. Both new factors (presence of CNT and ultrasound) can affect reaction kinetics, stability of suspension or the size of prepared particles. For example, ultrasound waves can open C=C bond of monomer, which starts polymerization initiation. Thus vinyl monomers (styrene, methyl methacrylate or vinyl acetate) can be polymerized without addition of initiator, only by application of ultrasound. This is called sonochemical polymerization method (15,33,34). 

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