| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a method for efficiently producing polybutylene terephthalate excellent in quality such as tone while suppressing generation of foreign matter by continuous esterification and subsequent continuous polycondensation. <P>SOLUTION: In the method for producing polybutylene terephthalate, polyester is continuously obtained through an esterification reaction step of esterifying a dicarboxylic component containing terephthalic acid as a main component and a diol component containing 1,4-butanediol as a main component in an esterification reaction tank, and a polycondensation reaction step of polycondensing a reaction product obtained in the esterification reaction step in a polycondensation reaction tank. As an esterification reaction catalyst, a titanium compound having a chelate ligand is used, and the titanium compound is directly added to a liquid phase portion in the esterification reaction tank. <P>COPYRIGHT: (C)2013,JPO&INPIT</p> |
