Polymer-embedded nanostructures

This outline of polymer-embedded cluster characterization is far from complete. Advances in nuclear magnetic resonance (NMR), SQUID-magnetometry, and many other characterization techniques are of considerable importance as well. In fact, the technological success of a nanostructured material depends strictly on the accurate characterization of its physical properties. 

For the comprehension of mechanisms involved in the appearance of novel properties in polymer-embedded metal nanostructures, their characterization represents the fundamental starting point. The microstructural characterization of nanofillers and nanocomposite materials is performed mainly by transmission electron microscopy (TEM), large-angle X-ray diffraction (XRD), and optical spectroscopy (UV-vis). These three techniques are very effective to determine particle morphology, crystal structure, composition, and grain size (48). 

On the other hand, magnetic polymer composites are components of sensor devices, due to the processability of polymers and to the enhanced magnetic attributes of the embedded nanostructures (Ergeneman et al. 2014). 

Figure 3. Various type of SERS active metallic nanostructures (a) metal-island films (b) metal-coated nanospheres (semi-nanoshells) (c) metal-coated random nanostructures and (d) polymer coatings embedded with metal nanoparticles. Inset An SEM image of silver-coated polystyrene spheres.

The nanoreplication of functional nanostructures has also been achieved through other block copolymer-templated structures. De Boer et al. [35] applied honeycomb-structured films of rod-coil block copolymer as patterned templates to replicate hexagonally packed arrays of aluminum cups on the substrate surfaces (Fig. 10b). Nguyen et al. [237] embedded semiconducting polymers in the channels of oriented hexagonal nanoporous silica and used this nanoscale architecture to control the energy transfer for potential optoelectronic applications. 

In this chapter there are presented two types of the nanocomposite materials the first one is the nanostructured composite with a structure of nanoparticles embedded in polymers, abbreviated to NIP, the second one is the nanocomposite with a structure of polymers deposited on nanopwrous thin films, called as PON. 

This kind of structure is undoubtedly very interesting since it is a nanostructure where nanospheres of acrylic/styrene polymer are embedded in a polyurethane-urea matrix. Such a structure suggests that very specific properties of the film could be obtained if the components of the hybrid were especially selected. 

Inorganic nanoparticles such as metal/semiconductors (M/SC) immobilized in polymer matrices have attracted considerable interest in recent years due to their distinct individualistic and cooperative properties [84]. Although the control of size and shape of M/SC nanoparticles has been widely investigated, the fundamental mechanism of nanostructural formation and evolution is still poorly understood. A novel cryochemical solid-state synthesis technique has been developed to produce M/SC nanocomposites [85]. This method is based on the low-temperature cocondensation of M/SC and monomer vapors, followed by the low-temperature solid-state polymerization of the cocondensates. As a result of the method of stabilizing the metal particle without requiring any specific coordination bonds between the particle surface and the polymer matrix, generated nanoparticles (Ag-nanocrystal mean size 50 A) were embedded in the polymer matrix with well-controlled shapes and a narrow size distribution [86]. 

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