Polarized Infra-Red Radiation as an Aid to the Structural Analysis of Long-Chain Polymers. I

Abstract

An experimental procedure is described for measuring dichroism in the infra-red spectrum of oriented materials. Oriented films of polythene, polyvinyl alcohol, polyvinyl chloride, polyvinyl acetate, and Nylon have been examined in the region 3600–700 cm−1, and the species (parallel or perpendicular) of many bands has been identified. The bearing of these results on current ideas concerning the structure of these polymers is discussed. A general result is that frequencies involving the motion of hydrogen atoms show rather low dichroism. On the other hand, very high dichroism has been found in some frequencies in which the motion is believed to be confined to other atoms.