Co-rotational

Bodo E, Gianturco F A and Paesani F 2000 Testing intermolecular potentials with scattering experiments He-CO rotationally inelastic collisions Z. Phys. Chem., A/F214 1013-34... 

Comparison of single-screw, co-rotating and counter-rotating twin-screw extruders... 

Fig. 4.16 Material flow path with co-rotating seres...

For a useful separation of pathways, the variation in final state distributions within each pathway must be at least somewhat smaller than the variation between pathways. The aforementioned dissociation of H2CO provides a perfect example of this technique, in which the H2 produced through the three-center ehmination leads to extensive rotational excitation of CO, with only moderate vibrational excitation of H2. By contrast, the competing pathway involving roaming of one H atom leaves much less energy in CO rotation, with very significant vibrational excitation of H2 [8]. 

By contrast, the dissociation channel leading to H + HCO (the radical channel) has no barrier and a dissociation threshold [49] of 30,328.5 cm. In 1993, van Zee et al. [50] found that excitation above this threshold led to CO rotational distributions that were bimodal. In addihon to the high-/ CO... 

Report 116 Compounding in Co-rotating Twin-Screw Extruders, Y. Wang, Tunghai University. 

PC PC/15% MWNT masterbatch 2 wt.% 105 2-cm Melt mixing in intermeshing co-rotating twin screw extruder... 

White, J. L., Kim, E. K., Keum, ]. M., and Jung, H. C., Modeling Heat Transfer in Screw Extrusion with Special Application to Modular Self-Wiping Co-Rotating Twin-Screw Extrusion, Polym. Eng. Set, 41, 1448 (2001)... 

The industrial use of twin-screw extruders for this purpose revolves extensively, but not exclusively, around intermeshing co-rotating variants. Closely in-termeshing counter-rotating designs are widely used for profile extrusion of UPVC dry-blends since they permit close temperature control and exhibit a high conveying efficiency due to the positive displacement of material where the screws intermesh [150]. 

Fig. 26. Typical mixing elements for a co-rotating intermeshing twin-screw extruder...

Fig. 27. Progressive dispersion of calcium carbonate in polypropylene within a co-rotating intermeshing twin-screw extruder. Filler dispersion is expressed in terms of a mean volume diameter determined by image analysis...

A mixture consisting of powdered polypropylene (59.91 g) and the step 1 product (90 mg) were tumble-mixed in a glass container for 24 hours. Thereafter the mixture (4.5 g) was compounded at 239°C using a small co-rotating twin-screw extruder. The sample required 4 minutes at a screw speed of 40rpm to be prepared. The extruded material only had a slight haze content. 

Figure 6 76 inch diameter E. B. Blue Co. rotational casting machine... 

---