Ionic liquids as Efficient Catalysts for The Glycolysis of Polyethylene Terephthalate

Abstract

THE GLYCOLYSIS of polyethylene terephthalate (PET) was …… studied using several ionic liquids as catalysts. The Lewis base ionic liquid, 1-butyl-3-methylimidazolium acetate [Bmim][OAc], exhibits higher catalytic activity for the glycolysis of PET, compared with 1-butyl-3 methylimidazolium chloride ([Bmim]Cl) and 1-butyl-3-methylimidazolium bromide ([Bmim]Br). The results revealed that the [Bmim][OAc] has a PET conversion of 75.1% and bis (2-hydroxyethyl) terephthalate (BHET) yield of 46.4% under the conditions of 1.0 g of [Bmim] [OAc] with 20 g of ethylene glycol in the presence of 2.0 g of PET at 180ºC after 2 hr of glycolysis. The main glycolysis product (BHET) was analyzed using XRD, NMR, EI-MS, FTIR, TGA and DSC.

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