Polyethylene terephthalate (PET) flakes are widely used as raw material for manufacturing of packaging materials. The
worldwide production of PET is 30.5 million metric tons/year. With such a large consumption, the effective application of PET
waste is of considerable commercial and technological significance. In this paper we used PET flakes for the synthesis of
unsaturated polyester resin to go green. PET flakes were depolymerized by using Neopentyl glycol (NPG) and propylene glycol
(PG). Glycolyzed product was reacted with maleic anhydride and phthalic anhydride. Then it was mixed with styrene monomer
to get unsaturated polyester (UP) resins. Molecular weight, Hydroxyl value and Acid value of all synthesized UP resins were
studied.
