| 摘要 |
A process for preparing molded articles of a polyimide is provided the steps of melting and extruding, at 50 DEG to 100 DEG C., a polyimide precursor composition for extrusion molding of a polyimide which includes 30 to 60% by weight of a polyimide precursor (c) obtained by reacting an aromatic tetracarboxylic dianhydride or its derivative (a) with an aromatic diamine or its derivative (b) in a good solvent of the polyimide precursor and then depositing the resultant polyimide precursor solution in a poor solvent of the polyimide precursor, 0.1 to 5% by weight of the poor solvent, and 35 to 69.9% by weight of the good solvent, and then heating the molded composition at 250 DEG to 500 DEG C. to imidate the same or its derivative (b) in a good solvent of the polyimide precursor and then depositing the resultant polyimide precursor (c) solution in a poor solvent of the polyimide precursor, 0.1 to 5% by weight of the poor solvent, and 35 to 69.9% by weight of the good solvent, and then heating the molded composition at 250 DEG to 500 DEG C. to imidate the same.
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