Abstract: A single flighted multi-screw conveying bushing that has only one helical screw element extending the length of the bushing. The bushing has a cross-section shape that has a segmented circular base and a lobe extending from the base. The lobe has a truncated crest that is sized to have a circumferential angle of from 15.degree. to 30.degree. and preferably from 22.degree. to 24.degree.. Also, a twin screw extruder having a pair of side by side drive shafts with at least two of the single flighted screw bushings mounted end to end on each shaft.

Abstract: To extract a liquid from a workable mass of material a first force is applied to the material in a first direction. A second opposed force is applied to the material within or slightly downstream of a liquid-extraction location. These opposed forces tend to compact the material to extract the liquid. The extracted liquid moves out of the liquid-extraction location along a path which extends generally transverse to the direction of the first and second forces. Third forces are applied to the material along the path in a direction generally opposite to that taken by the exiting liquid to prevent the material from traversing the path but to permit the liquid to exit. The first, second and third forces form a pinch point on the material within or slightly downstream of the liquid-extraction location to substantially obviate liquid flow countercurrent to the direction of the first force.

Abstract: An apparatus for extracting a liquid from a workable mass of material includes a first screw section for transporting the material, a second screw section which applies a force on the material in a direction generally opposite that of the transport direction, and a second screw extruder at or near a liquid extraction location which provides a pinch point on the material. The pinch point substantially eliminates liquid flow countercurrent to the material transport direction.

Abstract: Mass graft copolymerization carried out in an extrusion passageway having a sealing zone to prevent back flow of grafting material introduced to the extrusion passageway downstream of the sealing zone.

Abstract: An olefin copolymer rubber graft composition having a viscoelastic performance index of not greater than 100 as defined by the expressionPI=(DS.times.MV)/i.v.where DS is the die swell of the composition, MV is the melt viscosity of the composition and i.v. is the intrinsic viscosity of a resinous portion extracted from the composition.

Abstract: Mass graft copolymerization carried out in an extrusion passageway having a sealing zone to prevent back flow of grafting material introduced to the extrusion passageway downstream of the sealing zone.