Nanohybrids, functional materials

Sung Woo Hong was bom in Seoul, Republic of Korea, in 1976. He received his BS degree in polymer and fiber science in 2000 and PhD degree in materials science and engineering in 2007 from Seoul National University, Republic of lODrea. Since 2007, he has woilced as a postdoctoral fellow on polymer thin films and polymer physics in Prof. Thomas P. Russell s group at the Univereity of Massachusetts Amheret, USA. His research interests include polymer physics, self-assembly of nanomaterials, and synthesis of functional materials and oi anic/inoi anic nanohybrid materials and their applications. 

Advanced Functions of Nanohybrids of Biomolecules and Mesoporous Materials 141... 

Addition of third components to nanohybrids of proteins and mesoporous materials sometimes brings advantages in their functions. Kim, Hyeon, and coworkers immobilized enzyme molecules together with magnetite (Fe304) nanoparticles in hierarchically ordered, mesocellular, mesoporous silica (HMMS) (Figure 4.25)... 

The number of publications concerning utilization of the EISA process for fabrication of different structured materials is counted in the hundreds, which is far beyond the possibilities of this chapter to review in depth. Rather, we intend to provide a brief introduction into EISA and its application to the fabrication of functional thin films for electronic applications (e.g., electro-chromic layers and solar cells), with a special focus on fabrication of crystalline mesoporous films of metal oxides. Attention will also be given to techniques used to evaluate the pore structure of the thin films. For the other aspects of the EISA process, for example its mechanism,4 strategies for preparation of crystalline porous metal oxides,5 mesoporous nanohybrid materials,6 periodic organic silica materials,7,8 or postgrafting functionalization of mesoporous framework,9 we kindly recommend the reader to refer to the referenced comprehensive reviews. 

The present review is mainly concerned with the preparation and functionalization of micro compositional materials with cellulosic polysaccharides as the principal component, including four major categories graft copolymers, miscible or compatible polymer blends and networks, polysaccharide/inorganic nanohybrids, and mesomorphic ordered systems. Ultrathin layers of cellulosic... 

Clay minerals have developed into organic/inorganic, inorganic/inorganic, bio/inorganic nanohybrids through the modification of their interlayer space. Thus, layered clay minerals are the excellent materials for producing new functionality and structure like various nanohybrids. 

In the last decade, considerable progress was observed in the field of PO/compatibil-izer (predominantly on the base of PO-g-MA)/organo-surface-modified clay nanocomposites. Polyethylene (PE), polypropylene (PP), and ethylene-propylene (EP) rubber are one of the most widely used POs as matrix polymers in the preparation of nanocomposites [3,4,6,30-52]. The PO silicate/silica (other clay minerals, metal oxides, carbon nanotubes, or other nanoparticles) nanocomposite and nanohybrid materials, prepared using intercalation/exfoliation of functionalized polymers in situ processing and reactive extrusion systems, have attracted the interest of many academic and industrial researchers because they frequently exhibit unexpected hybrid properties synergisti-cally derived from the two components [9,12,38-43]. One of most promising composite systems are nanocomposites based on organic polymers (thermoplastics and thermosets). 

Abstract This review is dedicated to nanohybrid materials consisting of a polymer-based matrix and a disperse nanoscaled ceramic phase. Different preparation techniques for the synthesis of polymer-ceramic nanohybrid materials will be presented, such as blending techniques, sol-gel processing, in-situ polymeriza-ti(Mi, and self-assembly methods. Selected structural and functional properties of polymer-ceramic nanohybrid materials will be highlighted and discussed within the context of their dependence on parameters such as the homogeneity of the dispersion of the ceramic throughout the polymer matrix, the particle size of the ceramic phase, and the polymer-ceramic interface. Moreover, some advanced applications of polymer-ceramic nanohybrid materials will be addressed and compared with their polymeric counterparts. 

Keywords Functional properties Multifunctional materials Nanohybrid materials Polymer-ceramic interface Polymer-ceramic nanohybrids Structural properties Synthesis methods... 

The sol-gel synthesis of hybrid materials involves the occurrence of hydrolysis and condensation reactions in the presence of an organic polymer. Obviously, the selection of suitable polymer is of fundamental importance for the synthesis of the hybrid materials, as it should exhibit good miscibility with typical sol-gel precursors. The presence of suitable functional groups can facilitate the linkage between the polymer and the inorganic component. Also, the nature of the polymeric matrix is important because different properties of the matrix and, consequently, of the resulting nanohybrid material can be addressed for instance, the polymeric marix can be an elastomer (as in the case of polydimethylsiloxane) or thermoplastic (e.g., polytetrahydrofuran), amorphous, or (partially) crystalline [81]. 

Fig. 4 Fracture energy of epoxy-silica nanohybrid materials as a function of the silica loading, for nanoparticles of three different sizes (adapted fiom [267], open-access Elsevier)...

This paper summarizes the different preparative techniques for polymer-ceramic-based nanohybrid materials. Various classes and types of polymer-ceramic nanohybrid materials can be prepared using different techniques such as advanced blending techniques, in-situ polymerization, sol-gel-approaches, or self-assembly processes to yield nanohybrid materials with unique microstructures and properties, which are dictated in most cases by the nanoscale dimensions of the phases and by the interfaces between the polymeric matrix and the ceramic nanoparticles. Furthermore, selected structural and functional properties of polymer-ceramic nanohybrids as well as their advanced and prospective applications are addressed. 

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