Kneading Devices

Kneading Devices These are closely related to the agitated pan but differ as being primarily mixing devices with heat transfer a secondary consideration. Heat transfer is provided by jacketed construction of the main body and is effected by a coolant, hot water, or steam. These devices are applicable for the compounding of divided solids by mechanical rather than chemical action. Apphcation is largely in the pharmaceutical and food-processing industries. For a more complete description, illustrations, performance, and power requirements, refer to Sec. 19. 

When the polymer containing the maleic anhydride is introduced in the kneading device 3 min after mixing PPS and polymer, an increase in the torque is observed, which is attributed to a crosslinking reaction. When all the compounds are simultaneously mixed together, no crossUnking is observed [44]. The torque in dependence of time is iUustrated in Figure 5.4. In this way, it... 

In polymer processing, compaction is an important and necessary step in order to reduce the interparticle, unoccupied spaces and thus eliminate air. It is essential for melting in both single-screw extruders as well as for twin-rotor processors, as we shall see in Chapters 5 and 10. In twin-rotor devices, such as Co-TSEs, for example, the large and repeated deformation of compacted particulates by the kneading elements, which induces large plastic deformation of particulates, is the dominant melting mechanism. 

The first crushing machine, after the war club, was the mortar and pestle. Except as a laboratory implement, this has become more of a mixing device and is described under Mixing and Kneading. The bucking board of the assayer may be considered a mortar that has been flattened out. 

Also Mix-Muller. Originally, a device that used a heavy stone roller to grind and/or mix particulate solids. Today, a blender with one, two or four large metal rollers that mix and knead (densify) material. Often used prior to pressure agglomeration. (See also pan grinder.)... 

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