Analysis and Estimation of the Yield Stress of Dispersions
Yield stress affects mass transport, presents processing constraints during production and is responsible for functional performance of final products. Yield stress is of particular importance in suspensions and dispersions such as paints, printing, inks, catsup, salad dressings, cements, and clay slurries. The yield stress dominates the apparent viscosity at low shear rates, and is directly responsible for the coating characteristics, shape retention, and solvent holding capability of the dispersions. Yield stress also presents processing limitations in the form of material losses as residues remaining adhered to pipes and vessels, increased pumping requirements to initiate flow, and decreased overall rate or effects of processing. Yield stress remains a particularly important rheological property of suspensions and dispersions as it is a common and useful parameter for quality control, product identity, and for evaluating functional performance.
KeywordsShear Rate Liquid Bridge Interparticle Distance Interparticle Interaction Interparticle Force
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