| 摘要 |
A process for the production of polyolefin pellets by cuffing a raw material which contains a molten polyolefin resin and which is extruded from an extrusion orifice (121) of a die (12) into predetermined lengths with an underwater cutter (14) which is set in close vicinity to the die face of the die (12) and which rotates in water, satisfying the following requirements (A) to (C): (A) the average linear velocity (u) of the raw material passing through the extrusion orifice (121) as defined by the equation (Eq-1) is 50 to 650 mm/sec, (B) the fictitious aspect ratio (r) a L as defined by the equation (Eq-2) is 1.6 or below, and (C) the r/u value is 0.002 or above wherein Q is extrusion rate (mm3/sec) of the raw material per extrusion orifice; R is radius (mm) of the extrusion orifice; and t is cutting time (sec) defined as an inverse number of the product of the number of revolution of the under-water cutter and the number of blades of the cutter.
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