Polyelectrolytes nanocomposite with

Kalinina, N.A., Silinskaya, I.G., Kipper, A.I., Valueva, S.V., Kopeikin, VV, and Filippov, A.P. (2004) Structuring in aqueous solutions of anionic polyelectrolyte nanocomposites with zero-valence selenium nanoparticles a polarized light scattering study. Polymer Science Series A, 46, 857-862. 

Nanocomposites with carbon nanotubes have been an area of considerable R D ever since the excellent electrical and mechanical properties of carbon nanotubes were demonstrated. However, attempts to prepare carbon nanotube RPs often result in phase separation of the CNT and polymer phases causing premature material failure. Researchers at Nomadic Inc. and Oklahoma State University developed a layer-by-layer (LBL) assembly process that permits preparing polyelectrolyte/CNT RP with a CNT loading greater than 50 wt%. The excellent mechanical properties of these materials can be improved further by additional chemical action crosslinking of the CNT and polymer phases and by parallel alignment of the CNTs. The LBL method has been used to prepare various types of RPs. 

Table 3. Mechanical Properties of Track-Etched Membranes and Nanocomposites with Oriented Polyelectrolyte Nanodomains...

The other self-assembly method is layer-by-layer deposition. This method is also potentially interesting for complex superstructures creation. This method uses the oppositely charged polyelectrolytes to build multilayer stmctures from nanoparticles of various types. For instance, this method permits to fabricate the nanocomposites with magnetic luminescence. The Fc304 magnetic particles of 8.5 nm size were used as templates for the deposition of CdTe (QDs) quantum dots in polyelectrolyte during multilayers manufacturing [346],... 

Micrometer-sized hollow spheres with metal NPs (10-30 nm) were obtained by photoreduction of Ag in polyelectrolyte multilayers comprising Ag -PSS layers immobilized onto submicrometer-sized PS particles [138]. Hollow capsules with metal NPs can be formed either via a reduction of Ag followed by a core dissolution or by a core dissolution with a subsequent reduction of Ag. The formed spherical nanocomposites with silver NPs were stable for long time (over 3 months). The silver-based core-shell particles and hollow spheres may find interesting applications in catalysis and molecular photoprinting. The PEI-Pd ... 

Paranhos, C.M., Dahmouche, K., Zaioncz, S., Soares, B.G., and Pessan, L.A. (2008) Relationships between nanostructure and thermomechanical properties in poly (vinyl alcohol)/ montmorillonite nanocomposite with an entrapped polyelectrolyte. Journal of Polymer Science Part B Polymer Physics, 46, 2618-2629. 

Encapsulation via the layer-by-layer assembly of multilayered polyelectrolyte (PE) or PE/nanoparticle nanocomposite thin shells of catalase in bimodal mesoporous silica spheres is also described by Wang and Caruso [198]. The use of a bimodal mesoporous structure allows faster immobilization rates and greater enzyme immobilization capacity (20-40 wt%) in comparison with a monomodal structure. The activity of the encapsulated catalase was retained (70 % after 25 successive batch reactions) and its stability enhanced. 

McCarthy and coworkers126 229 reported a template-guided synthesis of water-soluble chiral PAn nanocomposites. The nanoparticles were prepared by the physical adsorption of aniline monomer onto a templating poly(acrylic acid) in the presence of (+)- or (-)-CSA, followed by chemical oxidation. Using this approach, optically active nanocomposites of approximately 100 nm diameter were formed. Earlier work by Sun and Yang230 using polyelectrolytes produced similar nonchiral dispersions in which the PAn chain is interwound with a water-soluble polymer by electrostatic forces.231 Similar work by Samuelson and coworkers utilized DNA as a chiral template for PAn.232... 

Caruso et al. [69] reported the preparation of negatively charged polystyrene latex particles (640 nm diameter) armored with a nanocomposite multilayer of Si02 nanoparticles (Ludox TM-40 26 4nm diameter) and poly(diallyldimethyl-ammonium chloride) (PDADMAC). These two components were sequentially adsorbed onto the surface of the polystyrene latex spheres (see Fig. 11), after adsorption of a precursor polyelectrolyte multilayer film of PDADMAC/... 

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