Chemical Recycling of Poly Ethylene Terphthalat to Obtain Unsaturated Polyester Resins

Abstract:Chemical recycling of Poly ethylene terphthalat (PET) was undertaken through catalytic glycolysis method and the obtained oligomers were used to prepare several unsaturated polyester resins. First, recycled PET in the presence of diethylene glycol (DEG), triethylene glycol (TEG) and zinc acetate as a catalyst was depolymerized, followed by purification of the products. The products were then reacted with maleic anhydride (MA), phthalic anhydride (PA), ethylene glycol (EG) and propylene glycol (PG) to obtain unsaturated polyester resins.In the glycolysis stage of PET, parameters like the type of glycol used and its molar ratio were examined and the hydroxyl value, free glycol and FT-IR spectrum of products were obtained. In the preparation of resins, parameters like the type of the products of glycolysis reaction and the usage of two different types of anhydride were studied. The prepared resins were then diluted with styrene and cured in the presence of suitable initiator.