应用化学 ›› 1994, Vol. 0 ›› Issue (1): 76-79.

• 研究论文 • 上一篇    下一篇

乳酸缩聚反应动力学

王勤, 张娟   

  1. 山东省医疗器械研究所 济南 250013
  • 收稿日期:1993-03-02 修回日期:1993-06-22 出版日期:1994-02-10 发布日期:1994-02-10

Kinetics of Polycondensation of Lactic Acid

Wang Qin, Zhang Juan   

  1. Shandong MedicaI Instrument Institute, Jinan 250013
  • Received:1993-03-02 Revised:1993-06-22 Published:1994-02-10 Online:1994-02-10

摘要: 乳酸直接缩聚制备聚乳酸的反应在124℃无外加催化剂时,在反应程度10%~60%的范围内符合3级反应,其动力学方程式为:=1.32×10-5[COOH]3在120℃,1%(wt)强酸性离子交换树脂作催化剂时,在反应程度10%~50%的范围内符合2级反应,其动力学方程式为:=1.51×10-4[COOH]2.

关键词: 乳酸, 缩聚反应, 动力学

Abstract: The kinetics of polycondensation of lactic acid has been investigated. The resuIts showed that in the absence of catalyst the polycondensation proceeds as a third order reaction at 124℃ with 10%~60%conversion:-d[COOH]/dt=1.32×1O-5[COOH]3. In the pres-ence of ca.1%(wt) of a strong acid ion-exchange resin at 120℃and 10%~50%of conver-sion the polycondensation follows a second order equation:-[COOH]/dt=1. 51 ×10-4[COOH]2.Addition of the catalyst decreased the activation energy of the reaction and thepolycondensation could be initiated at a lower temperature. The reaction showed a maximumrate as the amount of the catalvst was about 1%(wt)of the lactic acid.

Key words: lactic acid, polycondensation, kinetics