| 摘要 |
PROBLEM TO BE SOLVED: To obtain polymer pellets by controlling the occurrence of die swelling. SOLUTION: A polyester 12 is produced by a polycondensation reaction in a reactor 11. The polyester 12 is extruded in the shape of a strand from a die plate 27 by pressurizing the reactor 11 at 150 kPa. After the passage of a given time, the formation of the polymer strand is stabilized, and the occurrence of die swelling is controlled. When the pressure of the reactor 11 is increased to 500 kPa, the polymer strand, after being cooled in turn by a chute 31, is cut by a cutter blade 37 into the pellets. The pellets, after being dried by a centrifugal dryer 39, are blended in a housing tank 40 into uniform pellets. Since the extrusion of the polyester 12 is started under a low pressure, the occurrence of die swelling is controlled. |
