An X-Ray Study of Polyethylene at Pressures up to 14,000 kg/sq cm at 298 K.

Abstract

The diamond piston-anvil method was used to make x-ray wide angle diffraction studies of polyethylene at 298 K and at pressures up to 14,000 kg/sq cm. The data obtained was compared with the results of a study by Ito and Marui, and their observations (which were carried out at pressures up to 3000 kg/sq cm) were essentially confirmed. However, our data revealed that the linear-compressibility in the (110) and (200) directions did not vary with pressure in a linear fashion over the entire range. By ignoring strains in the chain direction, the volumetric strains as a function of pressure were calculated, and the data agreed well with the equation of state derived by Pastine for the crystalline phase of polyethylene. A value for the Gruneisen constant gamma sub o at atmospheric pressure and 298 K was calculated and a value gamma sub o = 3.64 was obtained. This agrees well with values obtained by Ito and Marui. No phase transition was observed at 298 C for the pressure range reported.

Document Details

Document Type
Technical Report
Publication Date
Mar 31, 1976
Accession Number
ADA024559

Entities

People

  • B. A. Newman
  • K. D. Pae
  • T. P. Sham

Organizations

  • Rutgers University–New Brunswick

Tags

DTIC Thesaurus Topics

  • Barometric Pressure
  • Compressive Properties
  • Dielectric Polymers
  • Diffraction
  • Equations
  • Gruneisen Parameter
  • Mathematics
  • Observation
  • Phase Transformations
  • Transitions
  • Wide Angles
  • X Rays

Readers

  • Materials Science and Engineering.