Rheology of PVC plastisols

PVC plastisols are suspensions of PVC resin in a hquid phase mainly constituted by the plasticizer and the stabilizer. Plastisols can be processed by different techniques, such as rotational casting, slush molding, dip molding, dip coating, or spray coating. In these pro- 

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Figure 10.29. Elastic and viscous moduli for PVC plastisols containing 5% (lower figures) and 10% (upper figures) recycled PVC. The particle size of the recycled PVC increases progressively from fraction 1 to fraction 4. x - blank sample, - Fraction 1, A - Fraction 2, O - Fraction 3, O - Fraction 4. [Reprinted from Polymer, Vol. 39, Garcia J.C., Marcilla A., Beltran M., The effect of adding processed PVC on the rheology of PVC plastisols, p. 2261-2267, 1998, with permission from Elsevier Science],...

Over a wide range of shear rate a plastisol may exhibit all three types of behavior since the viscosity of plastisols rarely displays true Newtonian behavior. At low shear rates they are generally pseudoplastic, at intermediate values they show dilatancy, and may sometimes become pseudoplastic again at higher shear rates, as shown in Figure 13. There is no certainty on the exact mechanism as the rheology of PVC plastisols is complex and affected by many factors such as... 

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