The rheology of vesicle and disk systems — Relations between macroscopic behaviour and microstructure

The presence of amphiphilic bilayers in the form of vesicles and disks typically has a profound effect on the rheology of the corresponding surfactant solutions. For instance such aggregates often show pronounced effects of shear thinning. These effects not only depend on the type of structure present, such as uni- or multilamellar vesicles, but in addition become more complicated due to the fact that shear may largely affect the structures present and thereby the rheological behaviour may depend to a large extent on the shear history of the given system. Such shear induced structural changes of bilayer systems are by themselves already very interesting and in addition lead to pronounced effects on the rheological behaviour.