| 摘要 |
PROBLEM TO BE SOLVED: To manufacture an aromatic polycarbonate containing an extremely small amount of foreign substances and a reduced amount of volatile substances without causing retention deterioration such as coloring, crosslinking or gelation in case of degassing the aromatic polycarbonate containing volatile substances by use of an intermeshing twin-screw extruder. SOLUTION: In a method for degassing not less than 80% of at least one of volatile substances contained in the aromatic polycarbonate by degassing the molten aromatic polycarbonate by means of a twin-screw extruder, increase of the amount of the foreign substances having a size of not less than 0.5μm contained in the treated aromatic polycarbonate is not more than 2,000/g in comparison with the amount of the foreign substances contained in the aromatic polycarbonate before the degassing treatment and the increase of amount of the gel contained in the treated aromatic polycarbonate is not more than 50/kg in comparison with the amount of the gel contained in the aromatic polycarbonate before the degassing treatment. COPYRIGHT: (C)2003,JPO
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