1. K. Zamaraev, R. Khairutdinov: Photoinduced Electron Tunneling Reactions in Chemistry and Biology 2. P. Suppan: The Marcus Inverted Region 3. H.D. Roth: Structure and Reactivity of Organic Radical Cations

Over the past four decades polymers containing imide groups (usually as build ing blocks of the polymer backbone) have attracted increasing interest of sci entists engaged in fundamental research as well as that of companies looking into their application and commercialization. This situation will apparently continue in the future and justifies that from time to time reviews be published which sum up the current state of knowledge in this field. Imide groups may impart a variety of useful properties to pol~'mers, e. g. , thermal stability chain stiffness, crystallinity, mesogenic properties, photoreactivity etc. These lead to a broad variety of potential applications. This broad and somewhat heteroge neous field is difficult to cover in one single review or monograph. A rather com prehensive monograph was edited four years ago by K. Mittal, mainly concen trating on procedures and properties of technical interest. Most reviews presented in this volume of Advances in Polymer Science focus on fundamen tal research and touch topics not intensively discussed in the monograph by K. Mittal. Therefore, the editor of this work hopes that the reader will appreci ate finding complementary information. Finally I wish to thank all the contributors who made this work possible and I would like to thank Dr. Gert Schwarz for the revision of the manuscripts of the contributions 3 and 4. Hamburg, September 1998 Hans R. Kricheldorf Contents Nanoporous Polyimides J. L. Hedrick, K. R. Carter, l. W. Labadie, R. D. Miller, W.

The basis for this volume is the 11th Symposium on Analytical Ultracentrifugation held in March 25-26, 1999 at the University of Potsdam, Germany. This book presents a comprehensive collection of 33 contributions from leading scientists in this field including:
Technical and methodological innovations.- Innovations in data analysis.- Hydrodynamics/Modelling.- Synthetic polymers, colloids and supramolecular systems.- Biological systems.- Interacting systems and assemblies.
In contrast to the increasing significance of analytical ultracentrifugation, related modern books are very rare. Therefore, this volume will be a helpful source of information to anyone who wants to catch up with the most recent developments and results related to this important analytical method.

In many cases rheological measurements are carried out in the simplest of geometries, but the interpretation involved in obtaining the rheological parameters of the test fluids from these measurements is surprisingly complex. The purpose of this book is to emphasise the points on which most workers in the field agree, and to let the authors deal with the contentious points according to their own beliefs and experience. This work represents a summary of the current thought on rheological meas urement by experts in the various techniques. When making measurements and obtaining from them parameters that describe the flow behaviour of the test fluids, it is essential that the experimentalist understands the underlying theory and shortcomings of the measurement technique, that he is aware of the likely microstructure of the fluid, and that from this he can appreciate how the fluid and the measuring system will interact with each other. It is this interaction that gives both the required rheological parameters of the fluids and the artefacts that confuse the issue. This book covers the main rheological measurement techniques from capillary, slit and stretching flows to rotational and oscillatory rheometry in various geometries including sliding plate measurements. These topics are backed up by chapters on more practical aspects, such as commercial instruments, and on computer control and data acquisition. The chapters deal with the basic methods, how the measurements are taken, and what assumptions and interpretations are made to obtain valid data on the test fluids."

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."

After epoxy resins and polyimides, cyanate esters arguably form the most well-developed group of high-temperature, thermosetting polymers. They possess a number of desirable performance characteristics which make them of increasing technological importance, where their somewhat higher costs are acceptable. The principal end uses for cyanate esters are as matrix resins for printed wiring board laminates and structural composites. For the electronics markets, the low dielectric loss characteristics, dimen sional stability at molten solder temperatures and excellent adhesion to conductor metals at temperatures up to 250 DegreesC, are desirable. In their use in aerospace composites, unmodified cyanate esters offer twice the frac ture toughness of multifunctional epoxies, while achieving a service tem perature intermediate between epoxy and bis-maleimide capabilities. Applications in radome construction and aircraft with reduced radar signatures utilize the unusually low capacitance properties of cyanate esters and associated low dissipation factors. While a number of commercial cyanate ester monomers and prepoly mers are now available, to date there has been no comprehensive review of the chemistry and recent technological applications of this versatile family of resins. The aims of the present text are to present these in a com pact, readable form. The work is primarily aimed at materials scientists and polymer technologists involved in research and development in the chemical, electronics, aerospace and adhesives industries. It is hoped that advanced undergraduates and postgraduates in polymer chemistry and technology, and materials science/technology will find it a useful introduc tion and source of reference in the course of their studies.

This volume includes 58 contributions to the 11th International Conference on Surface and Colloid Science, a highly successful conference sponsored by the International Association of Colloid and Interface Scientists and held in Iguassu Falls, Brazil, in September 2003. Topics covered are the following: Biocolloids and Biological Applications, Charged Particles and Interfaces, Colloid Stability, Colloidal Dispersions, Environmental Colloidal Science, Interfaces and Adsorption, Nanostructures and Nanotechnology, Self-Assembly and Structured Fluids, Surfactants and Polymers, Technology and Applications, Colloids and Surfaces in Oil Production. Surface and colloid science has acquired great momentum during the past twenty years and this volume is a good display of new results and new directions in this important area.

How did life begin on the Earth? The units of life are cells, which can be defined as bounded systems of molecules that capture energy and nutrients from the environment -- systems that expand, reproduce, and evolve over time, often into more complex systems. This book is the proceedings of a unique meeting, sponsored by NATO and held in Maratea, Italy, that brought together for the first time an international group of investigators who share an interest in how molecules self-assemble into supramolecular structures, and how those structures may have contributed to the origin of life. The book is written at a moderately technical level, appropriate for use by researchers and by students in upper-level undergraduate and graduate courses in biochemistry and molecular biology. The overall interest of its subject matter provides an excellent introduction for students who wish to understand how the foundational knowledge of chemistry and physics can be applied to one of the most fundamental questions now facing the scientific community. The editors are pioneers in defining what we mean by the living state, particularly the manner in which simple molecular systems can assume complex associations and functions, including the ability to reproduce. Each chapter of the book presents an up-to-date report of highly significant research. Two of the authors received medals from the National Academy of Science USA in 1994, and other research reported in the book has been featured in internationally recognized journals such Scientific American, Time, and Discover.

The broad field of conformational motion disorder in crystals is described with particular attention to the separation from the well known mesophases of liquid crystals and plastic crystals. Structure, thermodynamics and motion of a larger number of small and large molecules are discussed. Of special interest are the borderlines between smectic and high viscosity liquid crystals and condis crystals and between plastic crystals and condis crystals as complicated by pseudorotation, jumping between symmetry-related states and hindered rotation. This paper illustrates the wide distribution of conformational disorder in nature. Condis crystals and glasses ("Con"formational "Dis"order) can be found in small and large molecule systems made of organic, inorganic and biological compounds. The condis state was newly discovered only four years ago. In this article over 100 examples are discussed as example of the condis state. In many cases the condis state was suggested for the first time. Motion in the Condensed State, Condis Crystals and their Relation to Plastic Crystals, Condis Crystals of Flexible Macromolecules, Condis Crystals and their Relation to Liquid Crystals, Condis Crystals of Stiff Macromolecules.

Viscoelasticandtransportpropertiesofpolymersintheliquid(solution,melt)or liquid-like (rubber) state determine their processing and application to a large extent and are of basic physical interest [1-3]. An understanding of these dynamic properties at a molecular level, therefore, is of great importance. However,thisunderstandingiscomplicatedbythefactsthatdi?erentmotional processes may occur on di?erent length scales and that the dynamics are governed by universal chain properties as well as by the special chemical structure of the monomer units [4,5]. The earliest and simplest approach in this direction starts from Langevin equations with solutions comprising a spectrum of relaxation modes [1-4]. Special features are the incorporation of entropic forces (Rouse model, [6]) which relax uctuations of reduced entropy, and of hydrodynamic interactions (Zimm model, [7]) which couple segmental motions via long-range back ow elds in polymer solutions, and the inclusion of topological constraints or entanglements (reptation or tube model, [8-10]) which are mutually imposed within a dense ensemble of chains. Another approach, neglecting the details of the chemical structure and concentratingontheuniversalelementsofchainrelaxation,isbasedondynamic scalingconsiderations[4,11].Inparticularinpolymersolutions,thisapproach o?ers an elegant tool to specify the general trends of polymer dynamics, although it su?ers from the lack of a molecular interpretation. A real test of these theoretical approaches requires microscopic methods, which simultaneously give direct access to the space and time evolution of the segmental di?usion. Here, quasi-elastic scattering methods play a crucial role sincetheyallowthemeasurementofthecorrespondingcorrelationfunctions.In particular,thehigh-resolutionneutronspinecho(NSE)spectroscopy[12-15]is very suitable for such investigations since this method covers an appropriate range in time (0.005)t/ns)40) and space (r/nm [15). Furthermore, the possibilityoflabellingbyhydrogen-deuteriumexchangeallowstheobservation of single-chain behavior even in the melt.