초록 |
Recently, glycolysis has appeared to be an essential and commercial process for the recycling of waste PET plastic, in which transesterification occurs in the polymer chains with diols to form valuable products. The diols used in the glycolysis process vary from linear to rigid cyclic, bicyclic structures such as diethylene glycol (DEG), 1,4-cyclohexanedimethanol (CHDM), and D-isosorbide (ISB). In this study, we investigated the reactivity of diols toward transesterification/glycolysis reactions with PET and its model compound bis(2-hydroxyethyl) terephthalate (BHET). The influence of chemical structure was confirmed by considerably reduced reactivity in order of DEG, CHDM, ISB. The reaction rate for reactions involving DEG was 230 times and 1.2 times higher than that of CHDM and ISB, respectively. Besides, the glycolysis of terephthalate copolyesters consisting of ethylene glycol (EG), CHDM, and ISB moieties with DEG showed identified degradation rates as the above processes. |