| 摘要 |
PROBLEM TO BE SOLVED: To produce regenerated pellets having melt viscosity almost same to that of the original polyamide resin by minimizing the lowering of melt viscosity only by the operation of various conditions at the time of melt extrusion granulation of a cast polyamide resin without relying on a means adding an additive or sorting the cast polyamide resin. SOLUTION: In a method for producing regenerated pellets by melting scrap of a cast polyamide resin in a twin-screw extruder to extrude and granulate the same to produce regenerated pellets, the molten state in the extruder is held to a range satisfying the following various formulae 200T+880L/D+165t+792N/A+6600P<=80300, T<=300, L/D<=20, t<=260, N/Q<=100 and P<=2 [wherein T is a time (sec) stagnating a molten resin in the extruder, L is a distance (mm) stagnating the molten resin in the extruder, D is the diameter (mm) of the screw of a part where the molten resin is stagnated within the extruder, (t) is the temp. ( deg.C) of the molten resin, N is the rotational speed (rpm) of the screw, Q is extrusion quantity (kg/hr) and P is the volatile component ratio (wt.%) of the molten resin]. |
