发明名称 |
Process for production of polyamide |
摘要 |
In the process for producing polyamide of the present invention, a diamine and a dicarboxylic acid are melt-polycondensed in a batch-wise fist polymerizer in the absence of a solvent to produce a middle-stage polyamide. The diamine has a boiling point higher than a melting point of the middle-stage polyamide being produced under inner pressures of the first polymerizer. The middle-stage polyamide is fed into a continuous second polymerizer while controlling the change of relative viscosity within ±0.2, and further polycondensed there to produce the objective polyamide. With such a process, the change of polymerization degree of the middle-stage polyamide during the switching of the polymerization step from a batch-wise manner to a continuous manner is avoided, thereby preventing the variation in quality of the final product.
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申请公布号 |
US6657037(B2) |
申请公布日期 |
2003.12.02 |
申请号 |
US20020038587 |
申请日期 |
2002.01.08 |
申请人 |
MITSUBISHI GAS CHEMICAL COMPANY, INC. |
发明人 |
TANAKA KAZUMI;SHIDA TAKATOSHI;KUROSE HIDEYUKI |
分类号 |
C08G69/30;C08G69/04;C08G69/28;(IPC1-7):C08G69/02;C08G69/06 |
主分类号 |
C08G69/30 |
代理机构 |
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