摘要 |
This invention relates to a rotary kneading screw installed in an extruder kneading and extrusion-molding a material mixture of a synthetic resin such as polyester resin mixed with one or more of master-batch, calcium carbonate, talc and carbon fiber. Progressively higher pressures are applied to the material mixture passing through a kneading section defined in the rotary screw. This rotary kneading screw is thus capable of kneading and extruding the material mixture in a large amount without deteriorating its physical properties and without lowering fluidity and molecular weight thereof even where the material mixture is difficult to knead. |