A STUDY OF DYNAMIC BIREFRINGENCE IN POLYMERIC SOLIDS.

Abstract

The deformation of a polymer is accompanied by the orientation of molecules, crystals and crystalline superstructure. The case of such orientation affects the ability of the polymer to deform upon being subjected to stretch and will give rise to mechanisms of mechanical loss associated with maxima in the imaginary part of the dynamic modulus of elasticity. Tentative assignments of such loss mechanisms to molecular processes hs been previously made on the basis of dynamic mechanical studies. In the technique developed in this laboratory, birefringence (double refraction) measurements were made simultaneously with mechanical measurements. These are carried out during (a)relaxation at constant length, (b)deformation at constant strain rate, and (c)periodic strain at varying frequency. Equipment for measurements has been developed and tested. Preliminary molecular theories have been proposed. (Author, modified-PL).

Document Details

Document Type
Technical Report
Publication Date
Nov 04, 1963
Accession Number
AD0438545

Entities

People

  • Richard S. Stein

Organizations

  • University of Massachusetts Amherst

Tags

DTIC Thesaurus Topics

  • Birefringence
  • Elastic Properties
  • Frequency
  • Measurement
  • Modulus Of Elasticity
  • Molecules
  • Orientation (Direction)
  • Physical Properties
  • Refraction
  • Strain Rate
  • Superstructures

Fields of Study

  • Physics

Readers

  • Materials Science and Engineering.
  • Mechanical Engineering/Mechanics of Materials.