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Solid-State NMR is a branch of Nuclear Magnetic Resonance which is presently experiencing a phase of strongly increasing popularity. The most striking evidence is the large number of contributions from Solid-State Resonance atNMR meetings, approaching that ofliquid­ state resonance. Important progress can be observed in three areas: Methodological developments, applications to inorganic matter, and applications to organic matter. These developments are intented to be captured in three volumes in this series, each of them being devoted to more or less one of these areas. The present volume on Solid-State NMR III is devoted mainly to organic matter. The recent developments of deuteron NMR and their applications are reviewed in the first chapter. Crosspolarization, MAS, and dynamic angle spinning are being explored for enhancement of information and sensitivity. In addition to the analysis of classical relaxation times and modern 2D spectra, detailed dynamic information becomes accessible from investigations of the relaxation time anisotropies. The second chapter examines cross-polarization in static and rotating solids under conditions of spin diffusion and thermal motion. The underlying dipole-dipole interaction is further exploited by the techniques described in the third chapter for studies of polymer-polymer miscibility. Short­ range techniques are discriminated from long-range techniques based on spin diffusion. The use ofthese techniques is illustrated by a case study ofPMMAJPVF blends. The last chapter addresses novel z methods and applications of two-dimensional exchange NMR for investigations of relative molecular orientations, polymer morphology, molecular dynamics, and macroscopic molecular order.



2H-NMR Spectroscopy of Solids and Liquid Crystals

Deuteron Magnetic Resonance spectroscopy (2H-NMR) is an extremely powerful technique for investigating molecular structure and dynamics. This aticle covers the last five years (188–93) and reviews the 2H-NMR literature on molecular crystals, disordered materials and surfaces, inclusion compounds, and thermotropic and lyotropic liquid crystals. The current status of conventional experiments, development of new techniques, and applications to representative sytems are discussed, assessed and summarized.
G. L. Hoatson, R. L. Vold

Cross-Polarization, Relaxation Times and Spin-Diffusion in Rotating Solids

The cross-polarization technique in conjunction with sample spinning has been widely applied in high-resolution solid-state NMR studies. The present article reviews the major work performed during the last decade concerning the basic physical background and experimental intricacies of cross-polarization in rotation solids. The main focus is directed towards Hartmann-Hahn cross-polarization and nuclear spin systems containing spin-1/2 nuclei. However, in the introductory part a brief account is given regarding stutdies on quadrupolar nuclei and NMR techniques employing cross-polarization schemes and sample spinning with these nuclear species.
D. Michel, F. Engelke

Solid State NMR Techniques for the Study of Polymer-Polymer Miscibility

Different solid state NMR techniques for the study of the miscibility of polymer blends are reviewed. As an example of such a study of the experiments on the PMMA/PVF2blend are reviewed and discussed in a greater detail.
W. S. Veeman, W. E. J. R. Maas

Two-Dimensional Exchange NMR Spectroscopy in Polymer Research

In recent years the concept of two-dimensional exchange NMR spectroscopy, which is well-established as a tool for structural elucidation of biopolymers in solution, has successfully been applied to solid synthetic polymers. This review introduces the methodology of 2D exchange NMR in solids and illustrates its power by a number of experimental examples. Structural aspects include the packing of amorphous and frozen liquid-crystalline polymers as well as domain sizes in polymer blends. The unique information about slow molecular dynamics provided by 2D exchange NMR is demonstrated for the chain motion of polypropylene in both its crystalline and amorphous modifications. It is shown that 2D exchange NMR is also able to detect chain diffusion between crystalline and amorphous regions. As an example of new polymeric materials, the rotational motion of the discotic units in hairy rod macromolecules is presented. It is shown that the side-group motion in glassy poly(methyl methacrylate) is a rather complex process involving a coupling to a rocking motion of the main chain. Finally it is demonstrated that 2D exchange NMR can also be applied to determine the orientational distribution function in partially ordered polymers. Here a biaxially stretched film of poly(ethylene terephthalate) provides an illustrative example.
H. W. Beckham, H. W. Spiess


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