Nanostructured macromolecules systems

The property of the polymers in question to form nonspherical nanostructures was confirmed in experimental studies. Shih et al. [29] synthesized alternating copolymers of 1-alkenes with maleic anhydride. The maleic anhydride units were hydrolyzed to maleic acid units. Fully hydrolyzed macromolecules associated into microstructures of cylindrical and ellipselike shape. The cylindrical shape was characteristic of copolymers with octadecene and hexadecene moieties, while the copolymers with lower alkene copolymers (tetradecene, dodecene, decene, octene) formed ellipsoidal structures. Wataoka et al. [30] investigated the formation of nonspherical helices in a system of maltopentaose-carrying polystyrene (PS). The polymer was synthesized via the homopolymerization of vinylbenzyl maltopentaose amide (Scheme 3). 

When the composite-matrix is formed with a polystyrene solution as a dispersion medium, the self-assembly of silica particles is influenced by the adsorption of macromolecules on their surface. During adsorption, both solitary macromolecules and their aggregates transfer simultaneously onto the adsorbent surface. Depending on solution concentration, not only the conformation of adsorbed molecules but also the number and size of macromolecular aggregates in the solution change on adsorption. This leads to the formation of complex-shaped structures, which are linked by a system of nonvalent interactions and consist of polymeric-inorganic blocks[8,14] this is of interest in the preparation of a nanostructured medium (polystyrene-silica gel) as a precomposite for the fabrication of carbon structures in a matrix of silica particles. 

Peptoid nanostructures will be useful for investigating principles of macromolecule self-assembly and for fabricating novel functional architectures in biotic systems. 

The molecular organization of biopolymers is often much more complex than that of polymers synthesized in a chemical laboratory. Work is underway to systematically close this gap. Recent progress in controlled radical polymerization has made it possible to synthesize increasingly complex ionic macromolecules with controlled dimensions and topology. As a result, well-defined ionic block copolymers [10], colloidal [4] and molecular [8] PE brushes, and star-like PEs [9] have become available. In addition to emerging applications, such nanostructures constitute excellent model systems. 

Nanostructured materials are characterized by ordered structural domains,at the level of nanometers (7). These materials display the properties of condensed matter without a long range order. In general, four types of such materials based on the integral modulation dimensionalities of zero (nanoconfined particles), one (linear tunnel or channel structures two (multilayers) and three (nanophases) are possible (2). The simplest nanostructured materials are the nanoconfined systems of zero modulation dimensionality which consist of a host matrix with a nm-size spatial cavity that can act as an enclosure for dopant molecular particles. The nanostructured materials obtained by encapsulation of biological macromolecules in sol-gel derived porous Si02 structures that contain a trapped bioparticle represent a particularly novel and recent example in this category (5-4). 

It is nearly twenty five years since the application of Quantum Chemistry to the investigation of the catalytic properties of zeolites, yet it is still in its infancy with regard to the many basic questions relating to chemical changes in cavities of molecular dimensions. The recent emphasis on studies of the chemistry in nanostructures and reactions in nanocavities, is indicative of the importance of this field and its relation to biological systems in which chemical changes occur within the firework of macromolecules. 

Self-organization of macromolecules is one of the most popular way to achieve nanostructured features because it can be in principle applied to every kind of polymer, natural or synthetic [8], The recent advances in design criteria for the attainment of well-defined polymers and nanostructures allow to produce macromolecules with specific functionalities which are tailored for potentials in development of capsules, drug delivery systems and nanoscale electro-optical devices [9], Upon this premise, the methods that are able to induce the self-assembly of macromolecules are related to the chemico-physical properties of the selected polymer, of the substrate on which the nanostructure grows and on their combination. Obviously, this premise envisages the variety of different morphologies, nanostructures and related applications that can be obtained by the versatility of self-assembly. 

At present it is obvious that polymeric systems by virtue of the special features of their structure are always nanostructural systems [1]. However, treatment of such a structure can be different. The authors [2-4] used for this purpose the cluster model of the amorphous state structure of polymers [5-7], which supposes that the indicated structure consists of local order domains (clusters), immersed into a loosely packed matrix. In this case the latter is considered as a natural nanocomposite matrix and the clusters as a nanofiller. A cluster presents itself as a set of several densely packed collinear segments of various macromolecules with sizes up to several nanometres [5-7]. It has been shown that such clusters are true nanoparticles - the nanoworld objects (nanoclusters) [2],... 

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