Mechanical property improvement of UPE resin from glycolyzed PET with commercial UPE resin


  • Thidarat Limpiti Faculty of Science, Chulalongkorn University
  • Pranut Potiyaraj Faculty of Science, Chulalongkorn University, National Center of Excellence for Petroleum, Petrochemicals, and Advanced Materials, Chulalongkorn University


Petrography, Recycling, Glycolysis, Unsaturated polyester


The aim of this research paper is to improve mechanical properties of cured unsaturated polyester (UPE) resin prepared from glycolyzed PET by mixing with a commercial UPE resin. Postconsumer PET bottles were depolymerized by glycolysis reaction in excess propylene glycol at 190ºC in the presence of zinc acetate as a catalyst. The glycolyzed product was polyesterified with maleic anhydride and mixed with styrene monomer in order to obtain UPE resin. The prepared UPE resin was mixed with a commercially available general purpose grade UPE resin at various ratios. The mixed resins were cured using methyl ethyl ketone peroxide and cobalt octoate. Comparing between the prepared and commercial resins, it is most likely that the cured product from prepared resin possessed a higher crosslink density than the cured commercial resin. The results showed that the hardness of cured resin prepared from glycolyzed PET was slightly higher than that of the cured commercial resin. The addition of commercial resin did not affect the hardness of mixed resins. The impact strength and flexural strength increased as the amount of commercial resin increased. However, at higher than 60% by weight of the commercial resin, the improvement was leveled off.


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How to Cite

T. Limpiti and P. Potiyaraj, “Mechanical property improvement of UPE resin from glycolyzed PET with commercial UPE resin”, J Met Mater Miner, vol. 19, no. 1, Apr. 2017.



Original Research Articles