Preface

Summary

Since its inception, nuclear magnetic resonance (NMR) has been used with remarkable success to investigate polymeric materials. However, application to solid polymers was for many years largely the province of physicists and physical chemists because of the need for specialised spectrometers to gain access to the broad spectra (usually H) typical of solids, and because interpretation of these spectra and associated relaxation times required theoretical models of a strongly physical nature. The chemist, meanwhile, was more than satisfied to exploit the enormous potential provided by the increasing power of liquid-state NMR spectroscopy which had benefited considerably from the introduction of Fourier transform (FT) methods, the availability of higher fields generated by superconducting magnets with concomitant enhanced sensitivity, formidable on-line computing capabilities, and the added flexibility of multidimensional NMR. The rich site-specific information in high-resolution liquid-state NMR remained undetected in early solid-state spectra because of the dominant dipolar contribution. Sustained efforts to achieve comparable results for solids led to procedures to suppress dipolar contributions using high-power decoupling techniques, sample spinning and the application of ingenious pulse sequences. Today the full power of high-resolution one-, two- and three-dimensional NMR is available for solid materials, albeit requiring more sophisticated experimentation and analysis. Specifically, multidimensional NMR permits different spin interactions to be correlated or separated, exchange between different states of a resonant nucleus to be monitored over selected timeframes and the intricacies of complex molecular motions to be elucidated.