Nanotechnology and polymer nanocomposites — страница 5

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constitutes an interdisciplinary ensemble of several fields of the natural sciences that are, in and of themselves, actually highly specialized. Thus, physics plays an important role—alone in the construction of the microscope used to investigate such phenomena but above all in the laws of quantum mechanics. Prominent individuals in nanotechnology Richard Feynman - gave the first mention of some of the distinguishing concepts in a 1959 talk Norio Taniguchi - defined the term "nanotechnology" K. Eric Drexler - promoted the technological significance, described Grey goo scenario Robert Freitas - nanomedicine theorist Ralph Merkle - nanotechnology theorist Sumio Iijima - discoverer of nanotubes Richard Smalley - co-discoverer of buckminsterfullerene Harry Kroto -

co-discoverer of buckminsterfullerene Erwin Müller - invented the field ion microscope, and the atom probe. Gerd Binnig - co-inventor of the scanning tunneling microscope Heinrich Rohrer - co-inventor of the scanning tunneling microscope Paul Alivisatos - Director of the Materials Sciences Division at the Lawrence Berkeley National Laboratory Chris Phoenix - co-founder of the Center for Responsible Nanotechnology Mike Treder - co-founder of the Center for Responsible Nanotechnology Phaedon Avouris - first electronic devices made out of carbon nanotubes Alex Zettl - Built the first molecular motor based on carbon nanotubes NANOCOMPOSITES A rapidly growing area of nano-engineered materials provides a new dimension for plastics and composites Introduction The definition of

nano-composite material has broadened significantly to encompass a large variety of systems such as one-dimensional, two-dimensional, three-dimensional and amorphous materials, made of distinctly dissimilar components and mixed at the nanometer scale. The general class of nanocomposite organic/inorganic materials is a fast growing area of research. Significant effort is focused on the ability to obtain control of the nanoscale structures via innovative synthetic approaches. The properties of nano-composite materials depend not only on the properties of their individual parents but also on their morphology and interfacial characteristics. This rapidly expanding field is generating many exciting new materials with novel properties. The latter can derive by combining properties from

the parent constituents into a single material. There is also the possibility of new properties which are unknown in the parent constituent materials. The inorganic components can be three-dimensional framework systems such as zeolites, two-dimensional layered materials such as clays, metal oxides, metal phosphates, chalcogenides, and even one-dimensional and zero-dimensional materials such as (Mo3Se3-)n chains and clusters. Experimental work has generally shown that virtually all types and classes of nanocomposite materials lead to new and improved properties when compared to their macrocomposite counterparts. Therefore, nanocomposites promise new applications in many fields such as mechanically reinforced lightweight components, non-linear optics, battery cathodes and ionics,

nano-wires, sensors and other systems. The general class of organic/inorganic nanocomposites may also be of relevance to issues of bio-ceramics and biomineralization in which in-situ growth and polymerization of biopolymer and inorganic matrix is occurring. Finally, lamellar nanocomposites represent an extreme case of a composite in which interface interactions between the two phases are maximized. Since the remarkable properties of conventional composites are mainly due to interface interactions, the materials dealt with here could provide good model systems in which such interactions can be studied in detail using conventional bulk sample (as opposed to surface) techniques. By judiciously engineering the polymer-host interactions, nanocomposites may be produced with a broad

range of properties. Inorganic layered materials exist in great variety. They possess well defined, ordered intralamellar space potentially accessible by foreign species. This ability enables them to act as matrices or hosts for polymers, yielding interesting hybrid nano-composite materials.   Polymer Nanocomposites Materials and their development are fundamental to society. Major historical periods of society are ascribed to materials (i.e., stone age, bronze age, iron age, steel age [industrial revolution]; silicon age and silica age [telecom revolution]). Scientists will open the next societal frontiers not by understanding a particular material, but rather by understanding and optimizing the relative contributions afforded by material combinations. The nanoscale, and the