Preparation method of high molecular weight poly-morpholine-2,5-dione derivative and preparation method of the copolymer thereof

The invention discloses a preparation method of a high molecular weight poly-morpholine-2,5-dione derivative and a preparation method of the copolymer thereof. The preparation method of the high molecular weight poly-morpholine-2,5-dione derivative comprises the following steps: (1) morpholine-2,5-dione derivative, organic tin catalyst and dihydric alcohol are weighted and mixed to react to obtain the dihydroxy-terminal poly-morpholine-2,5-dione derivative after separation and purification; and (2) the dihydroxy-terminal poly-morpholine-2,5-dione derivative is mixed with a chain extender in proportion to react under air-isolated conditions to obtain the high molecular weight poly-morpholine-2,5-dione derivative. The high molecular weight poly-morpholine-2,5-dione derivative and the copolymer thereof prepared by the preparation methods have high molecular weight, biodegradability and good mechanical properties owning to high molecular weight, thereby meeting the requirement of the application of high molecular materials for medical use.