Acoustic properties and density of polyurea at pressure up to 13.5 GPa through Brillouin scattering spectroscopy
Abstract
Brillouin scattering was performed on an elastomeric polyurea, an important technological polymer. Being widely used for impact modification, of particular interest is its response to extreme pressure conditions. We applied pressures up to 13.5 GPa using a diamond anvil cell and measured the longitudinal and transverse sound velocities via Brillouin light scattering. From these data, the equation of state, the elastic moduli, and Poisson's ratio were obtained. By comparison with previous dilatometry measurements up to 1 GPa, we show how viscoelastic effects can be accounted for in order to obtain an accurate equation of state. Because of the extreme strain-rate hardening of vitrifying polyurea, the property changes associated with its solidification are more subtle in the high frequency Brillouin data than observed in conventional mechanical testing and dilatometry.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- May 18, 2018
- Source ID
- 10.1063/1.5031427
Entities
People
- C. Michael Roland
- Muhtar Ahart
- Russell J. Hemley
- Timothy Ransom
Organizations
- George Washington University
- Office of Naval Research
- United States Department of Energy
- United States Naval Research Laboratory