STRUCTURAL CHARACTERIZATION OF POLYALLENE IN THE SOLID-STATE AS STUDIED BY VARIABLE-TEMPERATURE HIGH-RESOLUTION C-13 NMR-SPECTROSCOPY

High-resolution C-13 NMR spectra of polyallenes in the solid state were measured over the temperature range from room temperature to 100-degrees-C by means of the variable-temperature cross polarization/magic angle spinning NMR and pulse saturation transfer/magic angle spinning NMR techniques. It was shown that the C-13 resonance lines of the noncrystalline, orthorhombic, monoclinic, and paracrystalline forms are chemically shifted from one another. On the basis of these peak assignments, the structural change was studied over the course of the temperature change.