Glassy relaxation internal viscosity

Here, the internal viscosity is defined as the contribution of the glassy-relaxation process to the zero-shear viscosity. This definition is different from the common understanding of the term used in literature/ although both have similar notions as to the existence of an effect of fast sub-Rouse-segmental motions on polymer viscoelasticity. In the literature the term internal viscosity generally refers to the effect that would lead to a plateau value of the intrinsic viscosity at high frequencies. 

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