| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a production method of glycolide, with which high-purity glycolide is obtained without lowering a rate of glycolide generation and with only a small amount of a by-product.SOLUTION: A production method of glycolide includes respective steps of: I. a step 1 to heat a mixture containing a glycolic acid oligomer and a polar organic solvent to a depolymerization temperature of the glycolic acid oligomer under normal pressure or reduced pressure; II. a step 2 to conduct depolymerization of the glycolic acid oligomer by further continuing heating at the temperature, and to co-distill the glycolide generated by depolymerization from the depolymerization reaction system containing the mixture together with the polar organic solvent to the outside of the depolymerization reaction system; and III. a step 3 to recover glycolide from the co-distillate, in which a catalyst is added in the step 2.</p> |
