Crystals and Crystallinity in Polymers

Crystals and Crystallinity in Polymers
Author: Claudio De Rosa
Publisher: John Wiley & Sons
Total Pages: 478
Release: 2013-08-26
Genre: Technology & Engineering
ISBN: 1118690796

Provides the tools needed to master and apply the fundamentals of polymer crystallography Using core concepts in physics, chemistry, polymer science and engineering, this book sheds new light on the complex field of polymer crystallography, enabling readers to evaluate polymer crystallization data and determine the best methods to use for their investigations. The authors set forth a variety of tested and proven methods for analyzing ordered and disordered structures in polymer crystals, including X-ray diffraction, electron diffraction, and microscopy. In addition to the basics, the book explores several advanced and emerging topics in the field such as symmetry breaking, frustration, and the principle of density-driven phase formation. Crystals and Crystallinity in Polymers introduces two new concepts in crystallinity and crystals in synthetic polymers. First, crystallinity in polymeric materials is compatible with the absence of true three-dimensional long-range order. Second, the disorder may be described as a structural feature, using the methods of X-ray scattering and electron diffraction analysis. The book begins by introducing the basic principles and methods for building structural models for the conformation of polymer crystal chains. Next, it covers: Packing of macromolecules in polymer crystals Methods for extracting structural parameters from diffraction data Defects and disorder in polymer crystals Analytical methods for diffuse scattering from disordered polymer structures Crystal habit Influence of crystal defects and structural disorder on the physical and mechanical properties of polymeric materials Crystals and Crystallinity in Polymers examines all the possible types of structural disorder generally present in polymer crystals and describes the influence of each kind of disorder on X-ray and electron diffraction patterns. Its comprehensive, expert coverage makes it possible for readers to learn and apply the fundamentals of polymer crystallography to solve a broad range of problems.

Chain Structure and Conformation of Macromolecules

Chain Structure and Conformation of Macromolecules
Author: Frank Bovey
Publisher: Elsevier
Total Pages: 270
Release: 2012-12-02
Genre: Science
ISBN: 0323158439

Chain Structure and Conformation of Macromolecules provides an introduction to the chain structures of synthetic polymers and their determination in solution and in the solid state. This book discusses the synthetic methods and polymerization mechanisms. Organized into eight chapters, this book begins with an overview of the brief history of the macromolecular concept and of stereochemical and geometrical isomerism in synthetic polymer chains. This text then introduces vibrational spectroscopy and nuclear magnetic resonance spectroscopy. Other chapters consider the geometric isomerism in diene copolymers as well as the rotational isomeric state method of calculation of polymer chain dimensions. This book discusses as well copolymerization and the measurement of copolymer structure. The final chapter deals with the NMR observation of polymers in the solid state by the method of magic angle spinning, by which both dynamic measurements and high resolution structural information are possible. This book is a valuable resource for organic chemists, chemical engineers, and research workers.

Conformational Properties of Macromolecules

Conformational Properties of Macromolecules
Author: A Hopfinger
Publisher: Elsevier
Total Pages: 352
Release: 2012-12-02
Genre: Science
ISBN: 032315459X

Conformational Properties of Macromolecules provides information about the molecular parameters and spatial and thermodynamic properties of macromolecules and the application of theoretical conformational energy calculations. The book covers topics such as macromolecular geometry, the classification of macromolecular structure, and the generation of macromolecular conformations and configurations; conformational energies and potential functions, induced dipole and polymer-solvent interactions; and conformational transition in molecules. Also covered are topics such as absorption and optical rotation spectroscopies, epitaxial crystallization of macromolecules, and conformational fluctuation in macromolecules. The text is recommended for structural chemists, X-ray crystallographers, biophysicists, physical chemists, and macromolecular scientists who would like to know more about this particular area of knowledge.

Conformation of Macromolecules

Conformation of Macromolecules
Author: Y. G. Medvedevskikh
Publisher: Nova Publishers
Total Pages: 270
Release: 2007
Genre: Science
ISBN: 9781600217555

Conformation is statistical property of the macromolecules consisting of a number of N structural units, links, position of which in a space one relatively to other is not inflexibly fixed by chemical bonds and assumes the possible random configurations. The number of possible configurations at N ” 1 is so great that permits to use the statistical methods at their analysis. That is why the conformation is a result of statistical averaging on all possible configurations of the macromolecule. It was for a long time notified and confirmed by computer modelling that the conformation of polymeric chain should be described by self-avoiding random walks statistics (SARW) but not Gaussian random walks statistics, assuming the phantom behaviour of polymeric chains. Nevertheless, Gaussian statistics is dominating at the analysis of thermodynamic, dynamic and kinetic stainings of the macromolecules conformation. This book will be useful for scientists who are engaged in the physical chemistry of polymers and their solutions.

Conformations

Conformations
Author: Alan E. Tonelli
Publisher: CRC Press
Total Pages: 223
Release: 2020-04-06
Genre: Science
ISBN: 1351336215

Among the materials found in Nature’s many diverse living organisms or produced by human industry, those made from polymers are dominant. In Nature, they are not only dominant, but they are, as well, uniquely necessary to life. Conformations: Connecting the Chemical Structures and Material Behaviors of Polymers explores how the detailed chemical structures of polymers can be characterized, how their microstructural-dependent conformational preferences can be evaluated, and how these conformational preferences can be connected to the behaviors and properties of their materials. The authors examine the connections between the microstructures of polymers and the rich variety of physical properties they evidence. Detailed polymer architectures, including the molecular bonding and geometries of backbone and side-chain groups, monomer stereo- and regiosequences, comonomer sequences, and branching, are explicitly considered in the analysis of the conformational characteristics of polymers. This valuable reference provides practicing materials engineers as well as polymer and materials science students a means of understanding the differences in behaviors and properties of materials made from chemically distinct polymers. This knowledge can assist the reader design polymers with chemical structures that lead to their desired material behaviors and properties.

Protein Conformational Dynamics

Protein Conformational Dynamics
Author: Ke-li Han
Publisher: Springer Science & Business Media
Total Pages: 488
Release: 2014-01-20
Genre: Medical
ISBN: 3319029703

This book discusses how biological molecules exert their function and regulate biological processes, with a clear focus on how conformational dynamics of proteins are critical in this respect. In the last decade, the advancements in computational biology, nuclear magnetic resonance including paramagnetic relaxation enhancement, and fluorescence-based ensemble/single-molecule techniques have shown that biological molecules (proteins, DNAs and RNAs) fluctuate under equilibrium conditions. The conformational and energetic spaces that these fluctuations explore likely contain active conformations that are critical for their function. More interestingly, these fluctuations can respond actively to external cues, which introduces layers of tight regulation on the biological processes that they dictate. A growing number of studies have suggested that conformational dynamics of proteins govern their role in regulating biological functions, examples of this regulation can be found in signal transduction, molecular recognition, apoptosis, protein / ion / other molecules translocation and gene expression. On the experimental side, the technical advances have offered deep insights into the conformational motions of a number of proteins. These studies greatly enrich our knowledge of the interplay between structure and function. On the theoretical side, novel approaches and detailed computational simulations have provided powerful tools in the study of enzyme catalysis, protein / drug design, protein / ion / other molecule translocation and protein folding/aggregation, to name but a few. This work contains detailed information, not only on the conformational motions of biological systems, but also on the potential governing forces of conformational dynamics (transient interactions, chemical and physical origins, thermodynamic properties). New developments in computational simulations will greatly enhance our understanding of how these molecules function in various biological events.

Dynamic Aspects of Conformation Changes in Biological Macromolecules

Dynamic Aspects of Conformation Changes in Biological Macromolecules
Author: C. Sadron
Publisher: Springer Science & Business Media
Total Pages: 511
Release: 2012-12-06
Genre: Science
ISBN: 9401025797

On the day after the 1959 Cambridge Congress, during which the International Union of Pure and Applied Biophysics was founded, a biophysics section was formed within the Society of Physical Chemistry (Societe de Chimie Physique). Since then, three of the Society's annual meetings (the 11th, 17th, and 23rd) were devoted exclusively to the physico-chemical study of biological systems. The first of these was held in June 1961 at a hotel in Col de Voza, at the foot of an alpine glacier above Chamonix. The second, in May 1967, took place in the more learned setting of the venerable rooms of the National Museum of Natural History in Paris. The third - the one dealt with in the present volume - was recently held at Orleans-La Source in the newly built lecture theatres of the young University, which is near the great Institutes of the National Centre for Scientific Research (CNRS), on the Sologne plateau. These three stages are milestones of an evolution which characterises (at least schematically) the explosive evolution of biological physico-chemistry. The first colloquium, with the title 'Deoxyribonucleic Acid: Structure, Synthesis and Functions', actually marks the first contact of the physical chemist with one of the then most prestigious biological macromolecules, the structure of which had just been discovered, and in this way celebrated one of the first and most striking successes of molecular biology.