Mixer, Maddock

The Maddock element, described in Chapter 7.4, is often (and possibly inappropriately) used as the standard for judging other mixers. This mixer does contribute to distributive 

Experiments described in Chapter 7 showed that although mixing is improved by the Maddock mixer, the striations (which were divided into segments at the mixer entry) remained aligned for most of the time with the direction of shear. 

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Zitzenbacher, G., Karlbauer, R., and Thiel, H., A New Calculation Model and Optimization Method for Maddock Mixers in Single-Screw Plasticating Technology, Int. Polym. Process., 22, 73 (2007)... 

Fig. 11.40 Extmdate of Blend 1 emerging from the SSMEE with a 3.5 L/D Maddock mixer operating at 140°C and 90rpm. [Reprinted hy permission from the Proceedings of the Fourth Semiannual Meeting of the Polymer Mixing Study, Polymer Processing Institute, Hohoken, NJ (1992).]...

Fig. 4.9 Extmsion screw mixing elements. Maddock mixer [55]. Saxton mixers [56]...

For a Maddock mixer with the flutes parallel to the axis of the screw, molten polymer flows into the in-flow flutes via a pressure gradient, and then either continues to flow downstream in the flute or is passed through a small clearance between the mixing flight and the barrel wall. 

The fitting of a Maddock mixer, planetary gear mixer, or cavity transfer mixer would not disperse the agglomerates. 

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