Evaluation of rheological properties and shear strength of modified plastisol by nano-silica and nano-calcium carbonate using Taguchi method

Plastisol is a suspension of small poly(vinyl chloride) particles, plasticizer, stabilizer, pigment and filler and can be used as a coating for the underbody insulator of cars. In this study, the influence of additives and fillers on the rheological and mechanical properties of plastisol were evaluated by Taguchi experimental design method, taking into account that the type and amount of PVC resin and plasticizer remained unchanged. The type of calcium carbonate and the amounts of nano-silica, solvent and liquid additive were investigated as the factors at three levels and the L9 array was used in the Taguchi design of experiment. Low and high-speed viscosities, the Bingham viscosity and the yield strength of the samples, as well as their shear resistance (shear strength) were measured. Nano-calcium carbonate increases the yield strength, Bingham viscosity and improves the flow of plastisol. The influence of liquid additive is better than that of nano-silica powder in improving the properties of plastisol. The solvent decreases the Bingham viscosity while having little effect on the yield strength of the plastisol. Nano-silica and nano-calcium carbonate have a great effect on the shear strength of plastisol and increase the shear strength.