Normal Vibrations of Polyacrylonitrile and Deuterated Polyacrylonitriles

摘要

Polarized infrared spectra of polyacrylonitrile, polyhyphen;agr;hyphen;deuteroacrylonitrile, polyhyphen;bgr;,bgr;hyphen;dideuteroacrylonitrile and polyhyphen;agr;,bgr;,bgr;hyphen;trideuteroacylonitrile have been measured in the region from 4000 to 200 cmmdash;1. bgr;,bgr;hyphen;dideuteroacrylonitrile was prepared by the hydrogen rehyphen;exchange reaction of agr;,bgr;,bgr;hyphen;trideuteroacrylonitrile with H2O in the presence of CaO. The calculations of the normal vibrations of polyacrylonitrile and these three polydeuteroacrylonitriles have been made, assuming a syndiotactic planar zigzag chain as the most simple model for calculation. The calculation was made by the use of theGFhyphen;matrix method with the Ureymdash;Bradley force field. The results show fairly good agreement between the observed and calculated frequencies. The assignments of the bands are given and discussed.