Memory Behavior of an Elastomeric Glass by Pressure- and Temperature-Perturbation Methods.
RUTGERS - THE STATE UNIV PISCATAWAY NJ HIGH PRESSURE MATERIALS RESEARCH LAB
Pagination or Media Count:
The memory behavior of structural relaxation of glass of Solithane 113 - a polyurethane elastomer, by pressure perturbation and also by temperature perturbation from an original state of pressure and temperature P,T of 2.5 KBar and 15 C, is reported. The Youngs modulus, obtained from the compressive stress-strain curves of the glassy samples, is used as a parameter to study its aging behavior. The liquid samples were transformed to a glass at a fixed point 2.0 KBar and 15 C. They were subjected to different hydrostatic pressure levels above 2.5 KBar, viz., 3.0, 4.0 and 4.5 KBar at 15 C and held at those pressure levels for 10 hours. The pressure was released to 2.5 KBar and the samples were then tested in compression after different aging time. Temperature perturbation experiments were carried out similarly, i.e. the samples at 2.5 KBar were initially annealed for 10 hours at lower temperatures, viz., 10 C, 5C and 0 C, heated back to 15 C and then tested after different aging time. In both cases, the perturbed glass shows higher initial Youngs modulus than that of unperturbed glass, followed by gradual decrease with aging time. All relaxation curves trace eventually back to the unperturbed with longer aging time. The higher the perturbation, the shorter it takes to trace back to the unperturbed.
- Elastomers and Rubber