Powder blending mixing efficiency

PHR in the case of plastisols. In dry blending, a flexible profile formulation for extrusion, it is imperative that the plasticizer added to the PVC resin gets fully absorbed, yielding a dry compound. A semidry powder blend can cause processing as well as conveying problems. The plasticizer absorption efficiency is related to the rate of heating of the resin-plasticizer mix, the type of resin, the particle size and distribution, the surface-volume ratio, and the type of plasticizer. Additives such as filler and impact modifiers also have an effect on plasticizer absorption. 

For highly viscous blends, the mixer needs to have a higher shear efficiency or to be heated at higher temperatures. In this case, the energy consumption is close to 100 kJ kg . Mixing or pulverization of pigments needs machines equipped with a friction blade mixing powders with liquids is done in turbomixers (Fig. 14.6). 

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