固相缩聚法生产聚酯中黏切片工艺分析

Technological analysis of mid-intrinsic viscosity PET chip prepared by solid polycondensation process

提出了用固相缩聚法生产聚酯中黏切片的新工艺。与熔融缩聚工艺流程相比,用新工艺生产的产品颗粒小,可提高固相反应速率；结晶度高(50%～55%),可省略使用过程中的结晶工序；乙醛含量低,约为熔融缩聚法的1/3,可提高最终产品的热稳定性。由于新工艺流程未使用有动力设备的最终缩聚釜,运行费用可减少20%,并减少了维修费用。

This paper presented a new technology for producing mid-intrinsic viscosity polyethylene terephthalate (PET) chip via solid polycondensation process. Compared with melt polycondensation process, the PET chip prepared with the new technology possessed following advantages: smaller particle size that benefited raising the solid phase reaction rate; high crystallinity up to 50%-55% that brought about saving the crystallization step in the application process and low acetic aldehyde content that only accounted for 1/3 of its counterpart prepared with melt polycondensation process, thereby the thermostability of the final product could be improved. In addition, 20% of the operation cost as well as the maintenance cost could be cut down because the final polycondensation reactor equipped with power facility was not adopted in the process flow of the new technology.