| 摘要 |
PROBLEM TO BE SOLVED: To provide a simple method for producing a polyhydroxycarboxylic acid industrially and efficiently at a high polycondensation rate, by which side reactions in the polycondensation are suppressed and the polyhydroxycarboxylic acid having a high molecular weight and high quality is produced. SOLUTION: This method for producing the polyhydroxycarboxylic acid comprises absorbing an inert gas in a molten polymer having ≥20,000 weight- average molecular weight and then carrying out the polycondensation under a reduced pressure. COPYRIGHT: (C)2003,JPO
|
