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Besides polymers, also other materials may show shear-thinning behavior. For dispersions, a shear process may cause orientation of particles into flow direction. Shearing may also cause disintegration of agglomerates or a change in the shape of particles (see Figure 3.13). Usually then, the effectivity of interactive forces between the particles is more and more reduced, which results in a decreasing flow resistance.

Note 1: Observation and visualization of flowing emulsions using a rheo-microscope

Deformation and flow behavior of droplets in flowing emulsions at defined shear conditions can be observed when using a rheo-microscope or other rheo-optical devices (like SALS; see Chapter 10.8.2.5). Corresponding photographic images are shown e. g. in [3.13] [3.15] [3.85].

Note 2: Visualization of flowing suspensions using polarized light imaging

Shear-induced particle orientation and alignment of particles can be tracked during flow by color changes resulting from the varying angle between the particle axis and the orientation of the polarizer/analyzer (see Chapter 10.8.2.1d; e. g. cellulose nanocrystals; between 100 nm and 200 nm long and around 10 nm thick).