减压法合成丙交酯的制备工艺优化研究

Research on the Optimization of Synthetic Technique for Lactide By Means of Decompression

由于可完全生物降解聚乳酸在生物医用材料和环保塑料方面的巨大潜在应用价值,使得合成聚乳酸的单体——丙交酯的研究成为一大热点。文章在丙交酯合成的传统工艺基础上,对减压法缩合D,L型乳酸成乳酸低聚体,进而裂解成二聚体即丙交酯的合成条件进行了优化。研究结果表明:工艺优化后得到的丙交酯粗产物在色泽方面明显优于传统工艺得到的丙交酯,而且在丙交酯产率方面有很大幅度的提高,在众多的工艺参数中反应系统的真空度和搅拌系统的搅拌速率起关键作用。

The biodegradable poly lactic acid enjoys great potential application value as biomedical materials and environmental plastics. As the monomer for poly lactic acid, lactide has been studied profoundly. In this paper, the optimization of synthetic technique for lactide was accomplished on the base of traditional technique-first the oligomer of lactic acid by condensation polymerization of D,L lactic acid, then lactide by splitting of lactic acid oligomer. Some achieved progresses were as follows: the initial lactide obtained by optimized technique enjoys brighter color than that obtained by traditional one. Meanwhile the production of lactide was improved a lot. Out of many technological parameters, the degree of vacuum and the stir rate are the key factors for the reacting of lactide.