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Stress Relaxation of Poly(ethylene Naphthalate): Isothermal, Isochronal and Isostructural Responses
Published
Author(s)
M L. Cerrada, G B. McKenna
Abstract
The physical aging response of polymers is generally examined in isothermal conditions by following the viscoelastic behavior as a function of aging time. It is then often asked if time-aging time superposition applies at a single temperature. If so, it can then be ascertained if time-temperature superposition applies to the aging time reduced curves obtained at different temperatures. In prior work from this laboratory we showed that isothermal time-aging time superposition did not apply to amorphous PEN. In this work we describe the surprising result that samples aged at 100 degrees C and then tested at 30 degrees C, 50 degrees C, 70 degrees C and 90 degrees C, that is iso-structurally (constant fictive temperature) seem to follow time-temperature superposition.
Cerrada, M.
and McKenna, G.
(2008),
Stress Relaxation of Poly(ethylene Naphthalate): Isothermal, Isochronal and Isostructural Responses, SPE Annual Technical Conference, Undefined
(Accessed October 24, 2025)