Nanocomposite defined

The interest in nanocomposites has increased markedly in recent years, due to the great potential associated with this relatively new group of materials. Nanocomposites, defined as compounds with reinforcement in the nanometer range (<100 nm), in at least one dimension, can be divided into three groups, depending on the geometrical shape of their nanoreinforcement ... 

A nanocomposite is defined as the composite of two materials, one having the dimension of nanometric level at least in one dimension. In polymer nanocomposites (PNC), the fillers are dispersed on a nanolevel. 

Synthesis of DNA-Au hybrid nanocomposites holds promise for applications in nanotechnology. Following the pioneering work of Mirkin et al., these modified Au nanopartides can act as useful building blocks to form spatially well-defined superstructures, including nanocrystals [108], binary and multilayered nanoparticle assemblies [109,110] and also well-ordered 3D nanoclusters [111]. 

Although the terms nanocomposite and hybrid are often used to define similar materials, we will use the classification indicated by Vilatelaand Eder [1], Nanocomposites are multiphase materials, in which one phase is dispersed in a second phase, resulting in a combination of the individual properties of the component materials. The volume fraction of the nanocarbon is typically less than a few percent. Nanocarbon hybrids are instead formed by both components with similar volume fractions. The inorganic compound (such as semiconductor nanoparticles) is deposited onto the surface of the... 

In this section, we consider the different synthesis routes that have been employed to incorporate polymers into LDH with emphasis on the in situ polymerization process, an approach which gives rise to well-defined nanocomposites. 

All these pathways give rise to poorly defined nanocomposites with only a few harmonics visible in the X-ray diffraction patterns. Generally, the polymer is found to influence strongly not only the textural properties but also the... 

Beside planar surfaces, Patten et al. [310-312] and Hallensleben et al. [313, 314, 322] prepared weU-defined nanocomposites by ATRSIP of from silica and gold nanoparticles. After spin-coating a solution of the polymer decorated particles onto mica, Hallensleben was able to image the single particles with the individual grafted polymer chains (Pig. 9.33). 

Highly structured, 3-D nanoparticle-polymer nanocomposites possess unique magnetic, electronic, and optical properties that differ from individual entities, providing new systems for the creation of nanodevices and biosensors (Murray et al. 2000 Shipway et al. 2000). The choice of assembly interactions is a key issue in order to obtain complete control over the thermodynamics of the assembled system. The introduction of reversible hydrogen bonding and flexible linear polymers into the bricks and mortar concept gave rise to system formation in near-equilibrium conditions, providing well-defined stmctures. 

It is necessary to note that the morphology of granular materials is extremely varied and it is defined by characteristics of materials, from which nanocomposite is composed, as well as by technological parameters of the manufacturing method and by the substrate properties. 

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