Metallized polymers, applications

The primary challenge facing adhesive bonding of metals is to obtain sufficient durability of a bonded structure. Initial bond strength in metal-polymer adhesive joints is almost invariably excellent. Challenging the application of adhesives in polymer-polymer joining, however, is the problem of obtaining a joint that is... 

Metallic polymers which are stable, soluble and processible, and therefore suitable for industrial applications ... 

The predominant applications of present day metal/polymer adhesion technology are for the development of strong metal-to-metal structural adhesive joints and durable protective coatings. 

The protonated form of poly(vinyl amine) (PVAm—HC1) has two advantages over many cationic polymers high cationic charge densities are possible and the pendent primary amines have high reactivity. It has been applied in water treatment, paper making, and textiles (qv). The protonated forms modified with low molecular weight aldehydes are useful as fines and filler retention agents and are in use with recycled fibers. As with all new products, unexpected applications, such as in clear antiperspirants, have been found. It is useful in many metal complexation applications (49). 

The initial hope for conducting polymers was that they would replace metals in applications as simple conductors. The interest for conducting coatings and radio-frequency shielding remains, but is so far held up by problems of instability and cost. Much work in this area is not published because it is carried out by the defence industries. 

This volume of the series focuses on the photochemistry and photophysics of metal-containing polymers. Metals imbedded within macromolecular protein matrices form the basis for the photosynthesis of plants. Metal-polymer complexes form the basis for many revolutionary advances occurring now. The contributors to many of these advances are authors of chapters in this volume. Application areas covered in this volume include nonlinear optical materials, solar cells, light-emitting diodes, photovoltaic cells, field-effect transistors, chemosensing devices, and biosensing devices. At the heart of each of these applications are metal atoms that allow the assembly to function as required. The use of boron-containing polymers in various electronic applications was described in Volume 8 of this series. 

The application we have in mind for the metal-polymer interfaces discussed in this book is primarily that where the polymer serves as the electroactive material (semiconductor) in an electronic device and the metal is the electric contact to the device. Metal-semiconductor interfaces, in general, have been the subject of intensive studies since the pioneering work of Schottky, Stromer and Waibel1, who were the first to explain the mechanisms behind the rectifying behaviour in this type of asymmetric electric contact. Today, there still occur developments in the understanding of the basic physics of the barrier formation at the interface, and a complete understanding of all the factors that determine the height of the (Schottky) barrier is still ahead of us2. 

Classification by End Use Chemical reactors are typically used for the synthesis of chemical intermediates for a variety of specialty (e.g., agricultural, pharmaceutical) or commodity (e.g., raw materials for polymers) applications. Polymerization reactors convert raw materials to polymers having a specific molecular weight and functionality. The difference between polymerization and chemical reactors is artificially based on the size of the molecule produced. Bioreactors utilize (often genetically manipulated) organisms to catalyze biotransformations either aerobically (in the presence of air) or anaerobically (without air present). Electrochemical reactors use electricity to drive desired reactions. Examples include synthesis of Na metal from NaCl and Al from bauxite ore. A variety of reactor types are employed for specialty materials synthesis applications (e.g., electronic, defense, and other). 

Halogenation and metallation of alkyl substituents may also be exploited. Chloroalkyl groups are formed by direct chlorination, thus providing a route to hydroxyalkylfurazans and their derivatives, while lithiation is the first step in the synthesis (Scheme 15) of aikylvinylfurazans suitable for polymer applications. 

The purpose of this paper is to introduce the technique of NEXAFS spectroscopy to scientists and engineers interested in the analysis of polymers and metal-polymer interfaces. NEXAFS is just coming into its own as a powerful tool for studying bonding interactions and molecular orientation of fairly complicated systems. By presenting background material and examples of applications to metal-polymer systems, it is hoped that the reader will be left with a basic understanding and an impression of the potential of this technique. 

During the last decade, there has been considerable interest in studying the interaction between ultraviolet radiation and polymers by the use of pulsed excimer laser (1-41. In fact, some attractive applications in microelectronics and surgery have been successfully implemented (5.), and further informations about the different mechanisms (photochemistry, thermal effect...) involved at the polymer surface have been invoked in order to elucidate their relative contributions. More recently, the attention has been focused on this type of polymer surface modifications to improve some surface properties like the adhesion in metallized polymer structures. 

Metallized polymers are used nowadays in numerous industrial applications (food packaging, capacitors, magnetic tapes etc...). The adhesion and the durability of metal/polymer systems represent the most important concepts that concern many research groups (1-3). Obviously, any aggressive medium which corrodes the metal film will be directly related to some loss of adhesion and durability. The aim of this work is to investigate the influence of corrosive environments on aluminum layers evaporated onto PET film and especially on both the A1 surface and interface. 

This book covers the theory behind formation of these ceramics, selection of materials, processing aspects, and their applications. The purpose is to encourage future research into CBCs using the theoretical and experimental methods outlined in this book. It is hoped that future research will establish CBCs as technologically important materials in a class similar to metals, polymers, and sintered ceramics. 

This movement is a key challenge for the entire field of advanced materials, but it is a particularly exciting challenge for silicon-based polymers. From the point of view of materials, silicon-based polymers span the three traditional domains plastics, ceramics, and metals. Potential applications are equally diverse. Silicon-based polymers range from structural materials, to optoelectronic devices, and to speciality materials for biomedical applications. We are in a unique position to capture the benefits of this merger of materials and polymer science. 

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