| 摘要 |
<P>PROBLEM TO BE SOLVED: To achieve a high molecular weight and a high optical purity without coloring. <P>SOLUTION: A lactic acid prepolymer is solid-phase polymerized in the presence of at least one phosphate catalyst selected from the group consisting of phenyl phosphate, phenylphosphonic acid, and fluorophosphoric acid. <P>COPYRIGHT: (C)2012,JPO&INPIT |
