Nanocompounds

Carbon black is reinforced in polymer and mbber engineering as filler since many decades. Automotive and tmck tires are the best examples of exploitation of carbon black in mbber components. Wu and Wang [28] studied that the interaction between carbon black and mbber macromolecules is better than that of nanoclay and mbber macromolecules, the bound mbber content of SBR-clay nanocompound with 30 phr is still of high interest. This could be ascribed to the huge surface area of clay dispersed at nanometer level and the largest aspect ratio of silicate layers, which result in the increased silicate layer networking [29-32]. 

Although the topic of sonoelectrochemistry will be treated in the subsequent section, it should also be mentioned that pulsed sonoelectroreduction of metallic salts gives rise to finely divided reactive metals which can be employed in organometallic synthesis see above [85]. The synthesis of nanocompounds of semiconductors such as cadmium and lead selenides can also be achieved using similar methodology [169]. 

NANOCELL Nanocompounds application to design of fuel cell membranes. 

Besides the above-described nanomaterial systems, various other types of nanoparticles have been reported using w/o microemulsions as templates suggesting the versatility of the microheterogeneous systems in synthesising nanocompounds. Typical examples of such preparations are described below. 

Electrochemical Synthesis of Quantum Dots and Semiconducting Nanocompounds... 

Attenuated total reflectance-Fourier transform infrared (ATR-FTIR) method can be used for spectral characterization of the physical properties of the synthetic mbber nanocompounds, as well as other complex samples such as polymer... 

RTP, based in Winona, MN, USA, was probably the first independent compounder to go into commercial production with nanocompounds. Most nanocomposites currently use nanoclay, although carbon nanotubes are becoming much more widespread. In the US, Southern Clay Products of Texas is a leading producer of nanoclays with products like Cloisite w hich are high aspect ratio additives based on montmorillonite, consisting of layered magnesium aluminium silicate platelets that have been surface treated to improve their compatibility with the polymer. 

In conclusion, from our point of view, the growing interest in the synthesis of novel metal transition or lanthanide based catalyst systems could offer novel opportunities for further improvements in the nanocompounding process by in-situ polymerization via Ziegler-Natta coordination catalysis. 

Specificity (Fig. 44.16) [94-96], The chemical and physical characterization of the " Tc nanostructures was based on the rhenium congeners. The hydrodynamic diameter of the nanopolymers increases with the polymer backbone functionalization (dextran 4.3 nm and final polymeric compounds 6.5-7 nm) and the overall charge was positive for the pyrazolyldiamine-dextran and negative for the cysteine-dextran derivatives. SPECT/CT studies in mice confirmed that the corresponding 99m pj,-iabeied dextran nanopolymers accumulate in the popliteal lymph node, allowing their clear visualization (Fig. 44.17). Therefore, these nanocompounds hold promising as radiopharmaceuticals for SEND and deserve further clinical evaluation. 

Keywords Atom mimicry Dendrimers Dendritic effects Hard/soft nanoelements Nanocompounds/assemblies Nano-periodic system Superatoms... 

These superatoms or atom mimics appear to fulfill a pivotal role as nanoscale building blocks, much as elemental atoms function at the pico- or subnanoscale level. As such, these poly(atomic) structures or entities have been classified and referred to as nano-element categories [137, 138]. Furthermore, these nanoelement categories have been shown to form stoichiometric nanocompounds or assemblies that exhibit well-defined intrinsic nano-periodic property patterns in much the same way as atomic elements and their compounds. 

From this basic list of 12 nano-element categories, a nano-element road map leading to three combinatorial libraries of nanocompounds and nano-assemblies can be envisioned, namely, [hard-hard], [hard-soft], and [soft-soft] types as illustrated in Fig. 18. These nanocompounds and nano-assembUes can be characterized analytically by the proportion of each of these 12 basic nano-elements they contain, based on their discrete bonding/assembly capacities, valencies, stoichiometries, and mass-combining ratios. Many examples of these stoichiometric nanocompounds and assemblies are already documented in the literature and are described in more detail elsewhere [137, 138]. 

As described above, a fourth feature anticipated by this new nano-periodic system was the expectation that members of these hard and soft nano-elemental categories, as well as their nanocompounds and assemblies would be expected to manifest certain well-defined nano-periodic property patterns. These property patterns were expected to be dependent on one or more of their CNDPs. Just as atomic... 

Combining Soft and Hard Nano-element Categories to Create Combinatorial Libraries of Nanocompounds and Nano-assemblies... 

Mimicry and Superatom Behavior by Forming 3D Nanoscale Lattices, Nanocompounds, and Nano-assemblies Reminiscent of Atomic Elements... 

Fig. 24 Proposed hard and soft particle nano-element categories and combinatorial libraries of possible nanocompounds. Nanocompounds indicated by an asterisk are described in the text (Sect. 6.4). Nanocompounds indicated by X have been reported in the literature and described...

Covalent, saturated-shell, nanocompounds (Fig. 26) can be prepared by a two-step approach involving, firstly, self-assembly of an excess of carboxylic acid-terminated dendrimers (i.e., shell reagent) around a limited amount of amine-terminated dendrimer (i.e., core reagent) in the presence of LiCl to form a... 

Pis. 27 Core-shell architecture of the PAMAM corerfullerene shell [S-l (H-5)3o] type of nanocompound. Z mdieates terminal -NH2 or -NH- groups on the PAMAM dendrimer core component of the core-shell nanocompound [177]... 

Dendrimer-(Fullerene) [S-l (H-5) ] Core-Shell-Type Nanocompounds... 

Covalent, stoichiometric [dendrimer core fullerene shell] nanocompotmds were readily formed by allowing a [core l,2-diaminoethane] (4 2) dendri-poly (amidoamine)-(NH2)64 (G = 4) PAMAM dendrimer to react with an excess of buckminsterfullerene (Ceo) [177]. In the presence of an excess of C o, only 30 Ceo moieties bonded to the dendrimer surface to produce a well-defined, stoichiometric [dendrimer (core) fuUerene (shell) ] nanocompotmd, i.e., [S-l (H-5)3o] core-shell-type as shown in Fig. 27. These structures were characterized extensively by MALDI-TOF, thermogravimetric analysis (TGA), UV-vis spectroscopy, and Fourier transform infirared (FTIR) spectroscopy. Such nanocompounds exhibited new fullerene-like solubility and photo-properties by readily generating singlet 02 in either aqueous or organic solvents. However, they offered other unique features such as larger size and nanocontainer-type properties that would normally be associated with the dendrimer core interior. 

Supramolecular Core-Shell Nanocompound [S-6 (S-4)2i3o] Exhibiting Well-Defined Stoichiometry Self-Assembly of an [S-4]-Type Protein Subunit Shell Around an [S-6]-Type ss-RNA Core... 

Fig. 34 Tobacco mosaic virus (TMV) an example of a well-defined nanocompound [S-6 (S-4)213o] consisting of an ss-RNA (core) and protein subunits (shell), with nanoscale dimensions of 18 nm diameter and 300 nm length, and a helical symmetry [195, 206]. Reproduced with...

---