Single-Parameter Aging in the Weakly Nonlinear Limit

  title={Single-Parameter Aging in the Weakly Nonlinear Limit},
  author={Saeed Mehri and Lorenzo Costigliola and Jeppe C. Dyre},
Physical aging deals with slow property changes over time caused by molecular rearrangements. This is relevant for non-crystalline materials such as polymers and inorganic glasses, both in production and during subsequent use. The Narayanaswamy theory from 1971 describes physical aging—an inherently nonlinear phenomenon—in terms of a linear convolution integral over the so-called material time ξ. The resulting “Tool–Narayanaswamy (TN) formalism” is generally recognized to provide an excellent… 

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