This and its companion Volume 2 chronicle the proceedings of the First Technical Conference on Polyimides: Synthesis, Char acterization and Applications held under the auspices of the Mid Hudson Section of the Society of Plastics Engineers at Ellenville, New York, November 10-12, 1982. In the last decade or so there has been an accelerated interest in the use of polyimides for a variety of applications in a number of widely differing technologies. The applications of polyimides range from aerospace to microelectronics to medical field, and this is attributed to the fact that polyimides offer certain desirable traits, inter alia, high temperature stability. Polyimides are used as organic insulators, as adhesives, as coat ings, in composites, just to name a few of their uses. Even a casual search of the literature will underscore the importance of this class of materials and the high tempo of R&D activity taking place in the area of polyimides. So it was deemed that a conference on polyimides was both timely and needed. This conference was designed to provide a forum for discussion of various ramifications of polyimides, to bring together scientists and technologists interested in all aspects of polyimides and thus to provide an opportunity for cross-pollination of ideas, and to highlight areas which needed further and intensi fied R&D efforts. If the comments from the attendees are a baro meter of the success of a conference, then this event was highly successful and fulfilled amply its stated objectives.

Pt. A: NMR and other Spectroscopic Methods. Pt. B: Mechanical Methods

This book arose from a symposium titled 'Transition Metal Carbides and Nitrides: Preparation, Properties, and Reactivity' organized by Jae Sung Lee, Masatoshi Nagai and myself. The symposium was part of the 1995 Congress of Pacific Rim Chemical Societies, held in Honolulu, Hawaii between December 17-22, 1995. The meeting was the first major conference to exclusively address the theme of metal carbides and nitrides, and brought together many of the major researchers in the field. Over 50 scientists and engineers reported their latest findings in five sessions of presentations and discussions. The book closely follows the topics covered in the conference: Theory of bonding Structure and composition Catalytic properties Physical properties New methods of preparation Spectroscopy and microscopy The book is unique in its coverage. It provides a general introduction to the properties and nature of the materials, but also covers their latest applications in a wide variety of fields. It should thus be of interest to both experts and nonexperts in the fields of material science, solid-state chemistry, physics, ceramics engineering, and catalysis. The first chapter gives an overview, and many of the chapters provide summaries of advanced topics. All contributions were peer-reviewed.

Over the past 40 years, Rotational Isomeric State (RIS) models for hundreds of polymer structures have been developed. The RIS approach is now available in several software packages. The user is often faced with the time-consuming task of finding appropriate RIS parameters from the literature. This book aims at easing this step by providing a comprehensive overview of the models available. It reviews the literature from the first applications of RIS models to the end of 1994, comprises synthetic as well as naturally orccuring macromolecules, and tabulates all the pertinent features of published models. It will help readers, even when not very familiar with the method, to take advantage of this computationally efficient way of assessing the conformational properties of macromolecular systems.

This book reviews recent advances in polymer swelling resulting from the use of novel microporous composite films. It offers a new approach to understanding sorption processes in polymer-liquid systems based on the molecular structures of the sorbed molecules and the repeat unit of the sorbent polymer. It is shown how the adsorption parameters obtained in these studies relate meaningfully with the Flory-Huggins interaction parameters. This implies that these adsorption parameters have relevance not only for swelling and drying of polymers, but also for other phenomena in which molecular sorption plays an important role, such as in chromatography and in membrane permeation.

Most of the untreated surfaces of polymers used in industry are not hydrophilic but hydrophobic. It is, therefore, difficult to bond these nonpolar polymer sur faces directly to other substances like adhesives, printing inks, and paints because they generally consist of polar compounds. On the other hand, polymer surfaces generally adsorb proteins when brought into direct contact with a bio logical system, resulting in cell attachment or platelet aggregation. The protein adsorption and attachment of biological components trigger a subsequent series of mostly adverse biological reactions toward the polymeric materials. Therefore, the technologies for surface modification of polymers or regulation of the polymer surface interaction with other substances have been of prime importance in polymer applications from the advent of polymer industries. Some of the technologies have been directed to introduction of new function alities onto polymer surfaces. The new functionalities introduced include improved surface hydrophilicity, hydrophobicity, bio compatibility, conductivi ty, anti-fogging, anti-fouling, grazing, surface hardness, surface roughness, adhesion, lubrication, and antistatic property. Theoretically, there is a large dif ference in properties between the surface and the bulk of a material and only the outermost surface is enough to be taken into consideration when the sur face properties are concerned. However, this is not the case for polymer surfaces, as the physical structure of the outermost polymer surface is generally not fixed but continuously changing with time due to the microscopic Brownian motion of polymer segments."

Natural products like wool, leather or cotton are permeable to water vapor. Their complex fibrous structure makes it difficult to imitate this natural phenomenon by synthesis. This book discusses ways to obtain water vapor permeability by microporosity or through a hydrophilic structure. Various areas of application include the medical sector for implants and dialysis, the industrial sector for filtration or for processes requiring the slow release of substances, and the consumer sector for leather substitutes or performance textiles.

In 1975, a symposium was held in Midland, Michigan, co-sponsored by the Dow Chemical Company and the then Midland Macromolecular Institute in honor of Raymond F. Boyer on the occasion of his 65th birthday and retirement from Dow. The topic of that first Boyer symposium dealt with an area of interest to Boyer, namely, polymer transitions and relaxations. One decade later, after ten years of additional fruitful scientific endeavor at MMI, Ray Boyer was again honored with a symposium, this time celebrating his 75th birthday and 10th anniversary at the Michigan Molecular Institute. The topic of the second Boyer symposium in 1985 was somewhat more focused, this time concentrating on the subject of order (or structure) in the amorphous state of polymers and the attendant polymer transitions that are observed. This volume contains the full manuscripts of the contributors to the 17th MMI International Symposium, held in Midland, Michigan on August 18-21, 1985. Eleven one-hour plenary lectures and ten 20-minute contributed papers were presented during the Symposium. An open forum panel discussion was also scheduled; the edited transcript of that session is included at the end of this volume. One of our tasks in organizing this Symposium was to attempt to gather together a number of speakers who would be able to define what, if any, physical structure might be present in anwrplwus polymers and what the nature of this order might be.

Until comparatively recently, trace analysis techniques were in general directed toward the determination of impurities in bulk materials. Methods were developed for very high relative sensitivity, and the values determined were average values. Sampling procedures were devised which eliminated the so-called sampling error. However, in the last decade or so, a number of developments have shown that, for many purposes, the distribution of defects within a material can confer important new properties on the material. Perhaps the most striking example of this is given by semiconductors; a whole new industry has emerged in barely twenty years based entirely on the controlled distribu tion of defects within what a few years before would have been regarded as a pure, homogeneous crystal. Other examples exist in biochemistry, metallurgy, polyiners and, of course, catalysis. In addition to this of the importance of distribution, there has also been a recognition growing awareness that physical defects are as important as chemical defects. (We are, of course, using the word defect to imply some dis continuity in the material, and not in any derogatory sense. ) This broadening of the field of interest led the Materials Advisory Board( I} to recommend a new definition for the discipline, "Materials Character ization," to encompass this wider concept of the determination of the structure and composition of materials. In characterizing a material, perhaps the most important special area of interest is the surface.

Everything flows, so rheology is a universal science. Even if we set aside claims of such width, there can be no doubt of its importance in polymers. It joins with chemistry in the polymerisation step but polymer engineering is supreme in all the succeeding steps. This is the area concerned with the fabrication of the polymer into articles or components, with their design to meet the needs in service, and with the long and short term performance of the article or component. This is a typical area of professional engineering activity, but one as yet without its proper complement of professional engineers. An understanding of polymer rheology is the key to effective design and material plus process selection, to efficient fabrication, and to satisfactory service, yet few engineers make adequate use of what is known and understood in polymer rheology. Its importance in the flow processes of fabrication is obvious. Less obvious, but equally important, are the rheological phenomena which determine the in-service performance. There is a gap between the polymer rheologist and the polymer engineer which is damaging to both parties and which contributes to a less than satisfactory use of polymers in our society. It is important that this gap be filled and this book makes an attempt to do so. It presents an outline of what is known in a concise and logical fashion. It does this starting from first principles and with the minimum use of complex mathematics.

'Recent Advances in Elastomeric Nanocomposites' reviews the recent progresses in the synthesis, processing as well as applications of elastomeric nanocomposites. Elastomers are a very important class of polymer materials and the generation of their nanocomposites by the incorporation of nano-filler has led to significant enhancement of their properties and, hence, expansion of their application potential. Most of the studies related with these materials are present in the form of research papers. Here, the authors present a comprehensive text covering the whole of the subject. The book is tailored more from the applications point of view, but also provide enough introductory material for research scholars new to this field.

The title of this volume implies a progression of sorts from species of molecular size to a product described on the basis of continuum prop erties. The difference in approach from the standpoint of molecular be havior, on the one hand-more the forte of chemists-and from the standpoint of large-scale properties, on the other-more the province of chemical engineers and materials scientists-represents a severe cultural divide, but one with much potential for creative input from both sides. Chapter 1 of this volume attempts a broad survey of trends toward the synthesis of large, well-defined molecular systems with interesting physical, chemical, or material properties. Review articles with more de tailed treatments are emphasized. In Chapter 2, Newkome and Moore field summarize work on synthesis of /I cascade" molecules. Next, Denti, Campagna, and Balzani describe the synthesis of assemblies with con nected metal-containing chromophore units which transmit electrons or electronic energy in defined ways. In Chapter 4 Wuest describes the con struction of hydrogen-bonded organic networks, and in Chapter 5 Michl defines a molecular-level construction set. Finally, Jaszczak points out how nature's attempts over geological time spans are emulated by recent human synthetic activity in the fullerene arena, through the appearance of various morphologies of natural graphite. The book concludes with a method for describing fractal-like mole cules, and an index based on the method for appropriate compounds described in the text."