| 摘要 |
<p>In a repeated batch production of palyamida, a dicarboxylic acid component and a diamine component fed to a batch reactor are melt-polymerized in the absence of solvent. After adding the diamine component to the molten dicarboxylic acid component, the melt polymerization is further continued at a temperature equal to or higher than the melting point of polyamide being produced for at least 10 min while maintaining the pressure of the vapor phase in the batch reactor at higher than 0.1 MPaG by introducing water vapor. The polyamide thus produced is hardly affected by gels even when the melt polymerization is conducted in the presence of polyamide remaining after the previous batch production. Molded articles thereof contain little fisheyes.</p> |
