Proton resonance spectra (220 MHz) and carbon-13 Fourier transform noise-decoupled spectra (22.6 MHz) of poly(vinyl alcohol) (PVA) were obtained. By examining the hydroxyl proton spectra in dimethyl sulfoxide solution, we have deduced triad tacticity of PVA. Moreover, the stereochemical sequence distributions in terms of triads and tetrads were determined from the methine and methylene carbon spectra, respectively. It was found that stereoregularity of radical-initiated polymerization of vinyl acetate is independent of the polymerization conditions but can be described by Bernoullian statistics.

High-resolution proton nmr spectroscopy was used to investigate the solution polymerization of cyclic ethers. The concentrations of secondary and tertiary oxonium ions, the propagating species, have been determined from nmr spectra. In "living" systems, where chain transfer and terminations are negligible, the kinetic molecular weight can also be monitored during the polymerization process. Molecular weight maxima were found in systems where the formation of tertiary oxonium ion is slower than the propagation. This method is generally applicable to study the Cationic polymerization of cyclic ethers which do not have proton peaks interfering with the oxonium ion signals.

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The theoretical values of the proton, carbon, and fluorine chemical shifts of the substituted benzenes with a variety of substituents have been calculated and compared with the experimentally observed chemical shifts. It is found that the para shieldings, as assumed, are primarily determined by the pi-electron density variations induced by the substituents. However, at ortho and meta positions, factors other than pi-electron densities become important in contributing to the observed shieldings. In disubstituted benzenes, it appears that the proposed additivity relationship of the substituent effects may be a combined effect of at least two separate additive mechanisms, one of which is from the pi-electron variation; both, however, contribute to the shieldings to an approximately equal extent.