Infrared spectra and assignments for polyvinyl chloride and deuterated analogs

Deuterated analogs of polyvinyl chloride (PVC) have been prepared and their infrared spectra analyzed as an aid to the more detailed assignment of bands in the spectrum of PVC. The following deuterated polymers were studied: PVC‐α d 1 , PVC‐β d 1 , PVC‐αβ d 2 , and PVC‐ d 3 . These, as well as PVC, were polymerized in urea‐complex, at −78°C., and at +50°C. in order to determine which bands are of crystalline origin and which of noncrystalline origin. Polarized spectra of oriented samples were obtained in each case to assist in the analysis. As a result of this study several of the previously uncertain assignments have been clarified. With the help of other studies on model chlorine‐containing compounds it has been possible to identify the various conformations present in the polymer and to associate these with isotactic and syndiotactic pair configurations in the chain. A method is suggested for determining the proportion of each type of pair configuration in PVC.