PBS polyester and preparation method thereof

The invention discloses PBS polyester and a preparation method thereof, polyester raw materials comprise succinic acid or a derivative thereof, 1, 4-butanediol zinc salt and magnesium salt, the molar ratio of magnesium element in the magnesium salt to succinic acid or the derivative thereof is 7.1 * 10 -3.5 * 10 : 1, and the molar ratio of zinc element in the zinc salt to succinic acid or the derivative thereof is 5.3 * 10 -1.3 * 10 : 1; the content of butanediol ether in the polyester is 0.4-2.2 wt%; the elongation at break of the polyester is greater than or equal to 250%; the preparation method comprises the following steps: mixing the raw materials, carrying out esterification and polycondensation reaction, and then extruding, pelletizing and drying to obtain the PBS polyester. Zinc salt and magnesium salt are added into the raw materials of the PBS polyester, so that the ether content in the polyester is increased, and the toughness of the polyester is improved. 本发明公开了一种PBS聚酯及其制备方法，所述