PDF全文下载：2011050509
李霞， 刘晨光*， 贺爱华
（青岛科技大学 橡塑材料与工程教育部重点实验室， 山东 青岛 266042）摘要： 研究了综合水解法和重结晶法纯化丙交酯，采用旋光仪对纯化后丙交酯进行表征。考察水解过程中去离子水的用量、水解时间及重结晶溶剂用量、时间、次数对重结晶结果的影响。水解法中，V(去离子水)∶m（粗丙交酯）=1∶1～1.5∶1(mL∶g), 最佳时间30～50 min；重结晶法中，V(乙酸乙酯)∶m(丙交酯)=1∶1（mL∶g），最佳结晶时间3～5 h；V(乙醇)∶m（丙交酯）=2∶1（mL∶g），最佳结晶时间3～5 h。乙醇体系重结晶产率可高出乙酸乙酯体系约10%，但丙交酯的光学纯度却远低于乙酸乙酯体系；重结晶次数越多，产率大幅降低，纯度略有增加。另外，比较了交替溶剂、混合溶剂、单一溶剂的影响。结果表明，交替溶剂比单一溶剂获得相对较高的重结晶产率和光学纯度,混合溶剂效果最差。
关键词： 丙交酯； 纯化； 水解法； 重结晶； 交替溶剂； 混合溶剂
中图分类号： TQ 317 文献标志码: AStudy on Purification of L-lactideLI Xia, LIU Chen-guang, HE Ai-hua
(Key Laboratory of Rubber-plastics, Ministry of Education, Qingdao University of Science and Technology,
Qingdao 266042, China)Abstract: A study was done on the purification of L-lactide by washing and recrystallization. All the factors in the purification process were discussed in detail, including time, dosage of deionized water in washing process, time and the dosage of solvent in recrystallization process and recrystallization times. In washing process, the ratio of V（H2O）∶ m（crude lactide） was 1∶1~1.5∶1(mL∶g) and the best washing time was 30~50 min; while in recrystallization process, the ratio of V（ethyl acetate）∶m（ lactide） was 1∶1 (mL∶g) and the best recrystallization time was 3~5 h and V（ethanol）∶m（ lactide） was 2∶1(mL∶g) and the best recrystallization time was 3~5 h, too. The purified lactide was characterized by Polarimeter. Results showed that the yield in ethanol was 10% much higher than that in ethyl acetate，but the optical purity of L-lactide is much lower than that in ethyl acetate. The yield had a sharp decrease with the increasing recrystallization times, and the optical purity just has a little increase. Besides, comparison of recrystallization results was made among alternating solvents, blends of solvents and single solvents. Results showed that the yield and optical purity in alternating solvent were best， while in blends of solvents were worst.
Key words: lactide; purification; washing; recrystallization; alternating solvents; blends of solvents
收稿日期： 2011-01-18
作者简介： 李霞（1984—），女，硕士研究生.*通信联系人.
