Rheological properties shear thickening

In wet grinding the power consumption is generally about 30 per cent lower than that for dry grinding and, additionally, the continuous removal of product as it is formed is facilitated. The rheological properties of the slurry are important and the performance tends to improve as the apparent viscosity increases, reaching an optimum at about 0.2 Pa.s. At very high volumetric concentrations (ca. 50 volume per cent), the fluid may exhibit shear-thickening behaviour or have a yield stress, and the behaviour may then be adversely affected. 

The apparent viscosity of PVC pastes varies with the shear rate applied, so that they rarely, if ever, exhibit truly Newtonian behaviour. The rheological properties of plastisols can range from pseudoplastic ( shear thinning ) to dilatent ( shear thickening ), as illustrated in Figure 107. 

Figure 12 shows that when the temperature is lower than 30°C, the interfacial shear viscosity increases as the shear rate increases. This phenomenon shows a dilatant behavior (shear thickening) as in a three-dimension system (12). These results fiirther prove that wax particles can contribute to the rheological properties of the interfacial film between... 

Uses Thickener, vise, stabilizer for factory- or in-store tinted paints, acrylic, vinyl acrylic or other water-based latexes Features For low to high shear rheology Properties Nonionic 0ptigel 800 [Sud-Chemie AG]... 

Just as with other properties, also rheological properties of PLCs are different - and more interesting than those of EPs. Shear thinning occurs at low shear rates, that is the viscosity decreases with increasing shear stress. The inverse phenomenon of shear thickening occurs occasionally. 

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