  The dynamic properties of a model transient network have been studied by
dynamic light scattering. The network is formed by microemulsion droplets
linked by telechelic polymers (modified hydrophilic polymers with two grafted
hydrophobic stickers). We compare the properties of two networks that are
similar but for the residence time of the hydrophobic stickers in the droplets.
The results are interpreted according to the so-called two-fluids model, which
was initially developed for semidilute polymer solutions and which we extend
here to any Maxwellian viscoelastic medium characterized by its elastic modulus
and terminal time as measured by rheology. This model is found to describe
consistently and quantitatively the experimental observations.
