Polymer structures nanostructure materials

New polymer structures allow the control of processability and final characteristics. For example, Mitsui is launching nanostructured metallocene alpha-olefins that have a crystallite size of the order of nanometres instead of microns as for conventional metallocene polyolefins. This yields a better balance of transparency, heat resistance, flexibility and elasticity characteristics. Targeted applications are automotive interior trim, packaging film, construction materials, protective films for electronic and optical parts, sealing products and as polymer modifiers. 

Similar approach has also been taken by Ferain and Legras [133,137,138] and De Pra et al. [139] to produce nanostructured materials based on the template of the membrane with etched pores. Polycarbonate film was also of use as the base membrane of the template, and micro- and nanopores were formed by precise control of the etching procedure. Their most resent report showed the successful formation of ultrasmall pores and electrodeposited materials of which sizes were as much as 20 nm [139]. Another attractive point of these studies is the deposited materials in the etched pores. Electrochemical polymerization of conjugated polymer materials was demonstrated in these studies, and the nanowires based on polypyrrole or polyaniline were formed with a fairly cylindrical shape reflecting the side wall structure of the etched pores. Figure 10 indicates the shape of the polypyrrole microwires with their dimension changes by the limitation of the thickness of the template. 

Examples of the use of nanostructured materials for packaging applications have been given in Chaudhry et al. (2008) and references therein. One of the first market entries into the food packaging arena was polymer composites containing clay nanoparticles (montmorillonite). The natural nanolayer structure of the clay particles impart improved barrier properties to the clay-polymer composite material. Some of the polymers which have been used in these composites for production of packaging bottles and films include polyamides, polyethylene vinyl acetate, epoxy resins, nylons, and polyethylene terephthalate. 

Doped materials, where a structural component of the material becomes partially substituted by a dopant species or when external species ingress in the original material as an interstitial ion. The term doping is thus applied to, for instance, yttria-doped zirconias used for potentiometric determination of O2 but also to describe the incorporation of Li in polymers and nanostructured carbons. 

Nanomaterials energy and applications As nanocrystals and nanotubes are better understood, it becomes possible to rationally design nano-structured materials for specific purposes. This area includes both chemical synthesis and physical properties of nanostructured materials incorporating fullerenes, organic conductive polymers, and inorganic nanostructures. A central goal is composite materials for solar energy utilization—new types of solar cells. 

The insertion of polymers, with electrical and ionic conductivity, into two-dimensional host structures continues to be a growing field of research in materials science/chemistry. As seen in this review, the technique of intercalation depends on the layered structure that is being investigated. It should also be pointed out that there is a huge repertoire of layered systems that is at the disposal of the researcher, providing the opportunity to create a wide range of nanostructured materials with specific applications. 

The development of nanostructured conductive polymers also requires the development of advanced characterisation techniques, and this aspect of current research is captured in several chapters. A detailed review of Atomic Force Microscopy (AFM) covers the wide range of related scanning probe microscopes that are particularly relevant to soft materials. It also shows how techniques such as conductive AFM go beyond structural measurements to image the functional properties of materials relevant to applications such as solar cells. A wide range of spectroscopic techniques has also been reviewed, showing how they can be applied to learn about the interactions between conductive polymers and nanostructured... 

Rocha e Silva et al. [52] have prepared layered PHB nanostructured materials by adding different amounts of commercial clays on PHB matrix. They have demonstrated that the obtained nanostructured materials exhibited an excellent degree of dispersion (intercalation/exfoliation) and that the clay was able to promote changes in the structure of neat polymer by reducing its crystallinity degree. 

The nanoscale structure of polyaniline nanofibers produces enhanced polymer functionalities their polymeric nature also yields new nanoscale physicochemical phenomena that have not been observed in inorganic nanostructured materials. In this section, a flash welding technique is presented based on an enhanced photothermal effect discovered with the polyaniline nanofibers. 

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