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.

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InhaltsangabePreface xi 1 Configuration and Conformation of Macromolecules in Polymer Crystals 1 1.1 Crystals of Polymers, 1 1.2 Constitution and Configuration of Crystalline Polymers, 3 1.2.1 Constitution, 3 1.2.2 Configuration, 5 1.2.3 Relative Configurations, 14 1.3 Conformation, 18 1.4 Relationships among Internal Parameters of Macromolecules, 19 1.5 Conformation of Polymer Chains in the Crystalline State, 21 1.5.1 Basic Principles, 21 1.5.2 The Equivalence Principle, 21 1.5.2.1 Symmetry Relations for Cylindrical Coordinates, 29 1.5.2.2 Application of the Equivalence Principle: Stereoregular Vinyl Polymers, 31 1.5.3 Principle of Minimum Conformational Internal Energy, 33 1.5.4 Relationships between Internal Coordinates and Conformational Parameters, 36 1.6 Helical Conformations in Isotactic and Syndiotactic Polymers, 46 1.7 Conformational Energy Calculations, 51 1.7.1 Setting Up Molecular Models: Coordinate Transformations, 52 1.7.2 Calculation of the Conformational Energy for Isotactic and Syndiotactic Polymers, 54 1.8 Helical Conformation and Optical Activity, 66 1.9 Alternating Copolymers, 68 1.10 Polydienes, 73 1.11 Nonhelical Chain Conformations of Isotactic Polymers, 78 References, 81 2 Packing of Macromolecules in Polymer Crystals 88 2.1 General Principles, 88 2.2 The Principle of Density (Entropy)-Driven Phase Formation in Polymers, 92 2.3 Symmetry Breaking, 96 2.4 Impact of Chain Folding on Crystal Structure Symmetry, 103 2.5 Frustrated Polymer Crystal Structures, 107 2.6 Chiral Crystallization of Polymers with Helical Chain Conformations, 110 2.7 Packing Effects on the Conformation of Polymer Chains in Crystals: The Case of Aliphatic Polyamides, 113 References, 118 3 Methods in Crystal Structure Determination from X-Ray Diffraction 123 3.1 XRay Diffraction of Semicrystalline Polymers, 123 3.1.1 Basic Principles, 123 3.1.2 Experimental Techniques for Polymer Crystals, 128 3.2 Fourier Synthesis and the Phase Problem in Crystallography, 134 3.3 XRay Fiber Diffraction Analysis, 140 3.3.1 Determination of the Fiber Period and the Bragg Distances of Diffraction Peaks, 140 3.3.2 Analysis of Nonhelical and Helical Structures, 142 3.3.3 The Structure Factor of a Single Molecule: The Continuous Helix, 144 3.3.4 CCV Formula for Helical Structures, 147 3.3.5 The Case of Incommensurable Helices, 153 3.3.6 Calculation of Structure Factors of a Single Helical Chain, 162 3.3.7 Calculation of Structure Factors of Crystals of Helical Molecules Including More Than One Chain per Unit Cell, 163 3.4 Determination of Parameters of the Unit Cell and Indexing of the Diffraction Pattern, 165 3.4.1 XRay Diffraction Data from Oriented Fibers, 165 3.4.2 XRay Diffraction Data from Powder Samples, 170 3.5 Measure of the Integrated Intensities of the Reflections and Corrections for Geometric (Lorentz), Polarization, and Absorption Factors, 171 3.6 Calculation of Structure Factors, 174 3.7 Structural Refinement, 180 3.8 Form of Diffraction Pattern and Broadening due to the Laue Function, 181 References, 183 4 Defects and Disorder in Polymer Crystals 185 4.1 Classification of Different Types of Structural Disorder, 185 4.2 Crystals with Partial Three-Dimensional Order (Class A): Disorder with Three-Dimensional Periodicity Maintained for Only Some Characterizing Points of the Structure, 191 4.2.1 Substitutional Isomorphism of Different Chains, 192 4.2.1.1 Disorder in the Positioning of Right- and Left-Handed Helical Chains, 192 4.2.1.2 Disorder in the Positioning of Up and Down Chains, 195 4.2.1.3 Disorder in the Orientation of Chains around the Chain Axis, 197 4.2.2 Substitutional Isomorphism of Different Monomeric Units, 200 4.2.3 Conformational Isomorphism, 202 4.2.4 Disorder in the Stacking of Ordered Layers of Chains (Stacking Fault Disorder), 204 4.2.4.1 Stac

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