| 摘要 |
<p>The objective of the present invention is to provide a method for efficiently producing a high-quality aliphatic polyester of which the molecular weight has been increased. In order to achieve this objective, the present invention provides a method that produces an aliphatic polyester having increased molecular weight, and that comprises: (i) a step in which an aliphatic polyester prepolymer having a number average molecular mass of at least 5000, a hydroxyl group as a terminal group, and succinic acid as at least one acid component, is poured into a mixing vessel, which is equipped with a diisocyanate injection portion, up to a position in the mixing vessel that exceeds the position of the injection portion, said aliphatic polyester prepolymer being poured in a liquid phase after having been melted at a temperature of at least the melting point thereof; (ii) a step in which the corresponding amount of diisocyanate corresponding to 1/10-2 times the equivalent amount of the hydroxyl groups in the aliphatic polyester prepolymer is injected from the injection portion; and (iii) a step in which the aliphatic polyester prepolymer and the diisocyanate are reacted.</p> |
