Elastic modulus of the transient network

Finally, at very high times the creep compliance starts to iiKiease linearly with time. This is the normal steady-state behavior for a liquid, where the strain rate (de/dt) is fxoportional to the stress o-. The ratio between the two is the viscosity, t) 

The time r when we cross from eq. (Vm.2) to eq. (Vm.3) is called the terminal relaxation time. It is the longest relaxation time observed in mechanical measurements. There seems to be a scaling form for the creep compliance that covers both the rubber and liquid regions 

If we compare the latter form with the viscous flow equation [eq. (VIII.3)], we are led to an important scaling relationship for the viscosity 

For long chains, the plateau modulus E is independent of chain length. When the chains are fully flexible, E essentially measures the number of entanglement points per unit volume in the tranaent network. Often the modulus in a melt is written as 

Another question of interest is the concentration dependence ofE if we go from melts = 1) to less concentrated solutions. The region 0.1 to 1 is probably complicated by many nonuniversal features, related to local monomer-monomer correlations. In the semi-dilute limit  

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