Zero-Shear Viscosity and Steady-State Compliance

5 Zero-Shear Viscosity and Steady-State Compliance 

Using the equations of linear viscoelasticity (Eqs. (4.30) and (4.63)), the zero-shear viscosity, 770, and the steady-state compliance, J°, can be numerically calculated from Eq. (9.19) by a computer program. If the molecular 

The effect of the primitive-chain contour length fluctuation was first considered by Doi. In an approach which was meant to be an approximation, Doi obtained the zero-shear viscosity and the steady-state compliance as 

Equations (9.26) and (9.27) are similar to Eqs. (9.24) and (9.25), respectively. Doi s calculation was mainly for the molecular-weight dependence of the zero-shear viscosity and the steady-state compliance. Because of the approximations involved in his approach, Doi s results do not converge to the Doi-Edwards theory (Eqs. (8.57) and (8.58)) at infinitely high molecular weight as Eqs. (9.24) and (9.25) do. 

Taking the contour-length-fluctuation effect into account, Doi obtained another expression for the viscosity 

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