EFFECTS OF TEMPERATURE, STRAIN RATE, AND SWELLING ON THE STRESS-STRAIN PROPERTIES OF ETHYLENE-PROPYLENE GUM VULCANIZATES OF VARYING CROSSLINK DENSITY
Abstract
The stress-strain properties and ultimate properties of EPR vulcanizates of varying cross-link density (swollen and un-swollen) were determined at two temperatures and two strain rates. A swell-deswell technique was employed to obtain equilibrium results at low volume fraction of rubber. The Mooney-Rivlin constants were found to depend on temperature, strain rate, and crosslink density. The network structural parameters obtained from swollen stress-strain curves were always greater than values obtained from the Mooney- Rivlin constants. Thermo elastic measurements showed that EPR undergoes a larger negative internal energy change on extension due to rotational energy levels within chains than polyethyene. A plot of the ultimate properties described a curve which was nearly independent of test conditions. The EPR curve was shifted in the direction of higher elongations.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 12, 1963
- Accession Number
- AD0414845
Entities
People
- T. J. Dudek
Organizations
- The Aerospace Corporation