Inorganic nanoparticle modification

The nanoparticles like Al O, ZnO, TiO, CaCO and SiO should also be modified chemically to increase their compatibihty with the polymer matrices. The hydrophilic nanoparticles are incompatible with polymers. The nanoparticle like TiO possess hydroxyl group on the surface. The high surface area of the nanoparticle and its high surface energy tends to the formation of a omerates, which lead to poor dispersion in the polymer matrix. 

The TiO nanoparticles can be modified by vinyltrimethoxysilane for dispersing in polyethylene matrix [37]. In a similar manner, the SiO nanoparticle is modified by the 3-aminopropyltrimethoxysilane and 3-glycydyloxypropyltrimethoxysilane to improve the mechanical properties [38] and fractme toughness [39] respectively. ZnO nanoparticle is modified by 3-(trimethoxysilyl) propyl methacrylate (TPMA) surfactant [34]. Researchers have also modified the CaCO nanoparticle with stearic acid to improve the compatibility with the polypropylene matrix [30,40]. 

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The same protocol based on aggregation of metallic particles may be used for detection and determination of various biomolecules and even simple inorganic ions. Antibodies, enzymes, biotin, streptavidin, or lectins can be used for nanoparticle modification [138] (Figure 16.24). 

PEI has also found use as a eoating for inorganic nanoparticles, either to impart eell-penetrating properties, as a platform for further modification or simply to provide cationic colloidal stabilization. Some reeent examples will be diseussed to exemplify the use of PEI as nanopartiele eoating. 

Kango S, Kalia S, Celli A, Njuguna J, Habibi Y, Kumar R (2013) Surface modification of inorganic nanoparticles for development of organic-inorganic nanocomposites—a review. Progr Polym Sci 38(8) 1232-1261... 

In the chapter Dispersion of Inorganic Nanoparticles in Polymer Matrices Challenges and Solutions, the synthesis, properties, and applications of nanoparticles their surface modification and preparation of polymer-inorganic nanocomposites are reviewed in detail. The chapter Recent Advances on Fibrous Clay-Based Nanocomposites reviews recent results on nanocomposite materials derived from the fibrous clay silicates sepiolite and palygorskite and combined with diverse types of polymers, from typical thermoplastics to biopolymers such as polysaccharides, proteins, lipids, and nucleic acids. The chapter Nanohybrid Materials by Electrospinning highlights recent progress and current issues in the production of... 

Selective permeability allows chemical reactions to be performed exclusively in the capsule interior. The in-situ modification of polyelectrolyte capsules by conducting syntheses inside inorganic nanoparticles creates a new class of multifunctional capsules that combines the properties of inorganic nanomaterials. These multifunctional, composite capsules may find applications for the protection, delivery, and storage of biochemical compounds that are unstable in solution or under UV/visible irradiation, where the use of capsules composed solely of polymeric components cannot be envisaged. Clearly, much further research is required in this area, most notably in understanding the mechanism of the chemical reactions that occur in the confined microsized geometric and diffusional limitations of polyelectrolyte multilayers. 

New class of microobjects synthesized by Layer-by-Layer assembly method has been observed. These are polyelectrolyte nanocomposite microcapsnles. The influence of microenvironment parameters pH and ionic force of a solution, structure of solvent and temperature) on the physical and chemical properties of polyelectrolyte capsules has been described. The basic approaches to capsulation of organic substances, based on the change of microcapsule environment properties, the approaches to modification of microcapsule shells to give them sensitivity to external influences have been observed and analyzed. Usually the inorganic nanoparticles are used for such modification of microcontainers. During our work the basic methods of nanocomposite capsules fabrication were described and the ways of microcapsule shell permeability control by external influences, such as electromagnetic irradiation and ultrasound were considered. 

Alternatively, particle-based systems include viral carriers, organic and inorganic nanoparticles, and peptides. Current trends indicate that particle-based systems will likely replace surface modifications as treatments move towards less invasive interventions, as evidenced by recent research attempting to ameliorate the shortfalls in drugeluting stent coatings with nanoparticle systems [8 10]. 

The chemical and physical modifications of inorganic nanoparticle and nanocarbon surfaces, therefore, have been extensively studied. The chemical modification of surfaces is permanent, but physical modification is temporary. We have pointed out that the dispersibility of silica nanoparticles and nanocarbons is extremely improved by surface grafting of polymers, namely, chemical binding of polymers, onto nanoparticle and nanocarbon surfaces (Tsubokawa, 1999 Tsubokawa, 2002 Tsubokawa, 2007). 

The importance of promoting better knowledge in the field of polymer composites is demonstrated by the contents of this volume, which contains 18 Independent chapters. The first part of this volume deals with the topic of structure and properties of polymer nanocomposites. In Chapter 1, Schulte et al. review the state of the art of carbon nanotube-reinforced polymers. The opportunity to apply carbon nanotubes as a filler for polymers and the improvement of the mechanical and functional properties are discussed. The application of non-layered nanoparticles in polymer modification is described by M. Q. Zhang et al. in Chapter 2. A grafting polymerization technique is applied to inorganic nanoparticles, which helps to provide the composites with balanced performance. Chapter 3, authored... 

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