Infrared Absorption Spectra of Alternating Copolymers of Butadiene with Acrylonitrile and Deuterated Analogs

Abstract

Abstract Random copolymers consisting of various amounts of butadiene and acrylonitrile have been prepared by conventional radical initiators or Ziegler—Natta catalysts. Recently, a novel alternating copolymer of butadiene with acrylonitrile was successfully prepared by the authors using a system of organoaluminum halide—transition metal compound as a catalyst. The NMR and x-ray analyses of the alternating copolymer indicated a high alternating regularity and trans regularity of the butadiene unit. Studies of mechanical properties of the copolymer suggested that the alternating copolymer was more flexible and stronger than the random copolymers. This report deals with a study of the ir spectra under stretching of the alternating copolymer influenced by the regularity of the molecular structure. The ir spectra of trans-1,4-polybutadiene have been studied by several authors and the assignments of the absorption bands of polyacrylonitrile have been given by Liang and Tadokoro et al. Tentative assignments of the absorption bands of the alternating copolymer were attempted on the basis of ir spectra and ir dichroism of partially deuterated copolymers and correlations with the results obtained on the above-mentioned homopolymers.