| 摘要 |
PROBLEM TO BE SOLVED: To provide an extruder which controls temperature rise caused by shear heat generation when a die passes without largely changing existing equipment, as a result, can control the gelation of a thermoplastic elastomer, reduce the specific power of an apparatus, and increase its treatment capacity, a pellet producing apparatus using the extruder, and a pellet producing method. SOLUTION: The extruder 4 has a cylinder 12 having at least one screw for sending the thermoplastic elastomer in the axial direction, and the die 20 which is fitted to the discharge part of the cylinder 12 and in which extrusion ports 22 for extruding a thermoplastic resin in the cylinder 12 into strands are formed. The extrusion port 22 has an inlet side large diameter part 24 and an outlet side small diameter 26. When the inside diameter of the small diameter part 26 is Do, the length in the axial direction of the part 26 is L, the sum of the cross-sectional areas of the large diameter parts in all the extrusion ports 22 formed in the die 20 is Ao, and the internal cross-sectional area of the cylinder 12 is Ac, the ratio L/Do is 2 or below, the ratio Ao/Ac is 0.01-0.07. |
