Polymer Bulletin

, Volume 76, Issue 1, pp 23–34 | Cite as

Glycolysis of poly(ethylene terephthalate) waste with diethyleneglycol under microwave irradiation and ZnSO4·7H2O catalyst

  • Cuong N. HoangEmail author
  • Thuyen T. N. Le
  • Quy D. HoangEmail author
Original Paper


The glycolysis of poly(ethylene terephthalate) (PET) by diethyleneglycol (DEG) in the presence of acetate catalyst usually produces a dark color product. Various catalysts have been used, but only ZnSO4·7H2O gives a bright yellowish liquid material. In addition, after the reaction the catalyst ZnSO4·7H2O can be separated easily and reused. Under microwave irradiation, the PET glycolysis is more efficient in time, conversion, and color improvement. The reaction mixture was purified by treatment with 20% sodium chloride solution. The structure of the isolated products was confirmed by FTIR, NMR, and HPLC-MS. Condensate of the volatile material from the glycolysis reaction was also isolated and analyzed by GC-MS. The mechanisms of PET degradation by DEG and side product formation were proposed. The transesterification of PET with excess DEG was strongly competed by the degradation of DEG to form dioxane and acetaldehyde as main volatile side products and by ether formation; therefore, the using of excessive DEG was unfavorable for the PET glycolysis.


Diethyleneglycol Microwave irradiation Recycled poly(ethylene terephthalate) ZnSO4·7H2O catalyst Glycolysis 



This research is funded by Vietnam National University HoChiMinh City (VNU-HCM) under Grant Number 562-2018-18-02.


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department of Polymer ChemistryUniversity of Science, VNU-HCMHoChiMinh CityVietnam
  2. 2.Department of Polymer and Composite MaterialsUniversity of Science, VNU-HCMHoChiMinh CityVietnam

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