公开(公告)号：US20210340318A1

公开(公告)日：2021-11-04

申请号：US17273650

申请日：2020-07-07

Applicant: LG CHEM, LTD.

Inventor： Woosung HWANG ,  Dongmin KIM ,  Seung Young PARK ,  Mi Kyung KIM ,  Joon Ho SHIN ,  Wonseok KIM

IPC: C08G64/34 ,  C08G64/40

Abstract: The present disclosure relates to a method for preparing a polyalkylene carbonate. More specifically, provided is a method for preparing a polyalkylene carbonate in which after polymerization of polyalkylene carbonate, a mixture from which unreacted carbon dioxide and residual catalyst have been removed is charged into a stripper to remove the unreacted epoxide compound, and then heat-exchanged before removing the solvent to increase the temperature of the mixture stream to the maximum level, which is subjected to a heating step, following by a solvent removal step, whereby the amount of steam required in the heating step is reduced, side reactions due to unreacted epoxide compounds are prevented, and steam energy can be reduced in the solvent removal step.