Twin screw extrusion intermeshing counterrotating

T. Sakai and N. Hashimoto, Application of Novel Counter-rotating Intermeshed Twin Extruder for Degassing Operation, SPE ANTEC Tech. Papers, 32, 860-863 (1986) also T. Sakai, N. Hashimoto, and N. Kobayashi, Experimental Comparison between Counterrotation and Co-rotation on the Twin Screw Extrusion Performance, SPE ANTEC Tech. Papers, 33, 146-151 (1987). 

The twin-screw injection molding extruder is an injection molding machine that is capable of both blending/compounding and extrusion in one step. Because it is a one step process, the fibers never go through the entire extrusion process as well as the pelletization that limits the fiber size, but are blended into the molten plastic before injection. The screw part of this machine is based on a non-intermeshing, counterrotating twin-screw extruder (Chapter 5). One of the screws in this machine is capable of axial movement and has a non-return valve on the end. This action enables the screw to inject and mold parts. 

For the reactive extrusion the Adiprene was heated to 50°C and subsequently fed to the extruder. The 1,4-butane diol was mixed with the catalyst di-butyltin dilaurate (0.03 weight percentage based on the amount of prepolymer). The mixture was fed to the extruder in a quantity ratio of 1 18 compared to the Adiprene. A 40 mm counterrotating closely intermeshing twin screw extruder was used with a L/D of 15. The screw rotation rate, the throughput and the die resistance were varied. The barrel temperature ranged from 80 to 110°C and the output varied between 2.1 and 4.1 kg/h. 

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