| 摘要 |
PROBLEM TO BE SOLVED: To obtain a polycarbonate granular material with a slight amount of the remaining organic solvent and improved melt molding processability and safety, and to provide a method for producing the material. SOLUTION: This method for producing a polycarbonate granular material comprises supplying a good solvent solution of a polycarbonate and a solidifying solvent therefor to warm water under stirring to yield an aqueous slurry of the polycarbonate granular material, separating water from the aqueous slurry, subjecting the resultant polycarbonate granular material to primary drying at 0-120 deg.C to volatilize the solvents, setting the amounts of the good solvent and the solidifying solvent included in the polycarbonate granular material at 1-10 wt.% and 1-10 wt.%, respectively, followed by subjecting the polycarbonate granular material to a secondary drying at 120 deg.C-170 deg.C. This polycarbonate granular material has a porocity of 20-50 volume % for small pores each 4 nm-1μm in diameter and a bulk density of 0.4-0.6 g/ml. The amounts of the good solvent and solidifying solvent included in the polycarbonate granular material are <=5 ppm and <=3,000 ppm, respectively, based on the polycarbonate granular material.
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