✦ LIBER ✦

Viscoelastic response of epoxy glasses subjected to different thermal treatments

✍ Scribed by Andre Lee; Gregory B. McKenna

Publisher: Society for Plastic Engineers
Year: 1990
Tongue: English
Weight: 431 KB
Volume: 30
Category: Article
ISSN: 0032-3888
DOI: 10.1002/pen.760300708

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✦ Synopsis

Abstract

Isothermal aging after a quench from above the glass‐transition temperature (T~g~) to below it was studied as a function of cross‐link density for model epoxy networks using small deformation stress relaxation experiments. We found that time‐aging time and time‐cross‐link density superposition principles described the changes observed in the Viscoelastic behavior of the epoxy networks. The aging response in the nonlinear Viscoelastic regime was also studied using creep experiments for one of the networks. It was found that upon aging near to the conventional glass‐transition temperature, the time required for the glass to age into structural equilibrium was independent of the magnitude of the applied stress. This result suggests that large stresses do not erase physical aging (or cause rejuvenation of the glasses).

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