Accession Number:

ADA052057

Title:

Brillouin Scattering and Segmental Motion of a Polymeric Liquid, I.

Descriptive Note:

Technical rept.,

Corporate Author:

UTAH UNIV SALT LAKE CITY DEPT OF CHEMISTRY

Personal Author(s):

Report Date:

1978-03-01

Pagination or Media Count:

32.0

Abstract:

The effect of segmental motion on the density-density correlation function of a viscous polymer liquid has been analyzed using a generalized relaxation equation developed by Zwanzig and Mori. It is shown that for polymer liquids of high viscosity Brillouin scattering is closely associated with the structural relaxation associated with the motion of chain segments. A single relaxation time theory is shown to yield good agreement with the experimental results on polypropylene glycol. The torsional motion involving a small number of monomer units is shown to be responsible for the dispersion and attenuation of the hypersonic wave. The fact that the Brillouin scattering spectrum of a polymer liquid is insensitive to the change of molecular weight is discussed. It is shown that temporal modulation of the spatial second moment of the intermolecular or inter-segmental interaction energy is responsible for the relaxation process involved in Brillouin scattering. Author

Subject Categories:

  • Physical Chemistry
  • Polymer Chemistry

Distribution Statement:

APPROVED FOR PUBLIC RELEASE