PATTERNS OF ALCOLYSIS OF SECONDARY POLYETHYLENE TEREPHTHALATE WITH DIETHYLENE GLYCOL

The aim of this work was to study the process of alcoholysis of recycled polyethylene terephthalate with diethylene glycol, as well as the structure and physicochemical properties of the final product. IR and PMR spectroscopy were used to study the structure and identify the structure of the products of RPET alcoholysis with diethylene glycol. As a result of  studies of the alcoholysis of polyethylene terephthalate-containing waste with diethylene glycol, a wide range of hydroxyl-containing oligoesters was synthesized. The possibility of changing their physicochemical properties by adjusting the process parameters was demonstrated. This makes it possible to synthesize hydroxyl-containing oligoesters with predetermined properties. The patterns of glycolysis of recycled polyethylene terephthalate with diethylene glycol were studied, and a material balance of the process was compiled and calculated. The physicochemical properties of the constituent fractions of the secondary PET degradation product were studied. It was found that the reaction products up to the stoichiometric ratio of the initial compounds are hydroxyl-containing fragments of macromolecules with residues of ethylene glycol and diethylene glycol at the ends; above the stoichiometric ratio of the initial substances with a large excess of diethylene glycol, they are fragments of macromolecules of terephthalic acid and ethylene glycol, as well as monomers of ethylene glycol and diethylene glycol.