Shearing equipment schematic

When polymers are subjected to a high shear stress in equipment, the random coil is severely distorted. In extreme cases, bond energies can be exceeded, and the polymer will break, or shear, as shown schematically in Fig. 5.6. This can happen in... 

Other low shear mixers use double or slanted cone and V-shaped vessels. Fig. 7.25 depicts schematically these always batch operating blenders which rotate about a horizontal axis. The lines and arrows in the sketches try to explain the particle paths that cause mixing. In Fig. 7.26 photographs of typical equipment are presented. 

Fig. 3 Process schematic for thermoplastic extrusion of ceramic bodies at EMPA. Depending on the process requirements in other applications of thermoplastic extrusion, the high shear mixer and single-screw extruder shown here can be replaced with pieces of equipment which have other operating principles, but perform the same function.

A common feature of all commercially available blending equipment (extruders, mills, internal mixers) is that polymer components have to experience a shearing deformation process in the molten state. Under the action of the shearing force, the dispersed elements are elongated and broken down as schematically shown in Fig, 1. 

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