NANOSCALE POLYMERIZATIONS

For the purpose of the basic research on electrophoretic transport phenomenon in brain, some basic researches have been carried out using alternatives such as collagen and agarose gels instead of a living mammalian brain [77]. In order to explore the similarity between the porosity of the brain s extracellular compartment and that of the nanoscale polymeric stmcture of the gel, slurry of fluorescent nanoparticles has been applied to monitor the distribution of the nanoparticles within the gel [78]. As seen in Figure 9-39, for example, the nanoparticles of Y203 Eu ... 

Yang, Y., Bugno, J., Hong, S. Nanoscale polymeric penetration enhancers in topical drug delivery. Polym. Chem. U.k. 4(9), 2651-2657 (2013). doi 10.1039/C3py00049d... 

There is currently considerable interest in processing polymeric composite materials filled with nanosized rigid particles. This class of material called "nanocomposites" describes two-phase materials where one of the phases has at least one dimension lower than 100 nm [13]. Because the building blocks of nanocomposites are of nanoscale, they have an enormous interface area. Due to this there are a lot of interfaces between two intermixed phases compared to usual microcomposites. In addition to this, the mean distance between the particles is also smaller due to their small size which favors filler-filler interactions [14]. Nanomaterials not only include metallic, bimetallic and metal oxide but also polymeric nanoparticles as well as advanced materials like carbon nanotubes and dendrimers. However considering environmetal hazards, research has been focused on various means which form the basis of green nanotechnology. 

Recent demands for polymeric materials request them to be multifunctional and high performance. Therefore, the research and development of composite materials have become more important because single-polymeric materials can never satisfy such requests. Especially, nanocomposite materials where nanoscale fillers are incorporated with polymeric materials draw much more attention, which accelerates the development of evaluation techniques that have nanometer-scale resolution." To date, transmission electron microscopy (TEM) has been widely used for this purpose, while the technique never catches mechanical information of such materials in general. The realization of much-higher-performance materials requires the evaluation technique that enables us to investigate morphological and mechanical properties at the same time. AFM must be an appropriate candidate because it has almost comparable resolution with TEM. Furthermore, mechanical properties can be readily obtained by AFM due to the fact that the sharp probe tip attached to soft cantilever directly touches the surface of materials in question. Therefore, many of polymer researchers have started to use this novel technique." In this section, we introduce the results using the method described in Section 21.3.3 on CB-reinforced NR. 

Figure 3. Schematic representation of the micro- and nanoscale morphology of gel-type (a) and macroreticular (b) resins [13], Level 1 is the representation of the dry materials. Level 2 is the representation of the microporous swollen materials at the same linear scale swelling involves the whole polymeric mass in the gel-type resin (2a) and the macropore walls in the macroreticular resin (2b). The morphology of the swollen polymer mass is similar in both gel-type and macroreticular resins (3a,b). Nanopores are actually formed by the void space surrounding the polymeric chains, as shown in level 4, and are a few nanometer wide. (Reprinted from Ref [12], 2003, with permission from Elsevier.)...

Dovidenko, K. Potyrailo, R. A. Grande, J., Focused ion beam microscope as an analytical tool for nanoscale characterization of gradient formulated polymeric sensor materials, In Combinatorial Methods and Informatics in Materials Science. Materials Research Society Symposium Proceedings Fasolka, M. Wang, Q. Potyrailo, R. A. Chikyow, T. Schubert, U. 

Many hydrogenation and polymerization reactions in the chemical industry are carried out with liquid-phase reactants. An example is the hydrogenation of aliphatic dinitriles to produce diamines (108,109), which are subsequently converted with adipic acid in solution and polymerized to produce linear polyamides, including nylon 6,6. Recently, the development of wet-environmental transmission electron microscopy (wet-ETEM) for direct nanoscale probing of... 

Control over the material s shape at the nanoscale enables further control over reactants access to the dopant, and ultimately affords a potent means of controlling function which is analogous to that parsimoniously employed by Nature to synthesize materials with myriad function with a surprisingly low number of material s building blocks. A nice illustration is offered by the extrusion catalytic polymerization of ethylene within the hexagonal channels of MCM-41 mesoporous silica doped with catalyst titanocene.36 The structure is made of amorphous silica walls spatially arranged into periodic arrays with high surface area (up to 1400 m2g 1) and mesopore volume >0.7 mLg-1. In this case, restricted conformation dictates polymerization the pore diameter... 

Abstract Dye-doped polymeric micro- and nanobeads represent smart analytical tools that have become very popular recently. They enable noninvasive contactless sensing and imaging of various analytical parameters on a nanoscale and are also widely employed in composite sensing materials, in suspension arrays, and as labels. This contribution gives an overview of materials and techniques used for preparation of dye-doped polymeric beads. It also provides examples of bead materials and their applications for optical sensing and imaging. 

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