| 摘要 |
PROBLEM TO BE SOLVED: To produce the subject granulate product capable of providing a dehydrated polycarbonate resin granular product having a little amount of powder, good filterability and low amount of residual solvent by specifying a temperature of a vessel and mixing conditions in the vessel when obtaining the polymer granular product from a polycarbonate organic solvent solution in the vessel. SOLUTION: This method comprises continuously feeding an organic solvent solution for polycarbonate into a vessel holding a polycarbonate granular product and hot water under a mixing condition and then evaporating the solvent. When evaporated, it is necessary to keep a temperature of the vessel at T1 to T2 deg.C defined by formula I and II (M1 is a mean molecular weight of 13,000 to 20,000; and M2 is a mean molecular weight of >=20,000) and to employ mixing conditions having a mixing speed of 60 to 100 rpm and mixing power of 5 to 10 kw/hr.m<3> . The vessel is pref. a horizontally axial twin-screw mixer, and its mixing paddle is pref. of ribbon type. The organic solvent is pref. methylene chloride. |
