Biomaterial based polyhydric compounds were synthesized and utilized for the depolymerization of PET. Three different oligomers were synthesized by using 5, 15 and 25% PET. Depolymerized oligomers were esterified with dehydrated castor oil (DCO) fatty acids to give polyester polyols. Polyurethane adhesives were synthesized using these polyols for joining rubber-rubber assembly. Bond strength was measured by 180degrees peel test. Mode of failure was studied by scanning electron microscopy (SEM) analysis. Depolymerised PET oligomers, polyols and polyurethane were characterized by FTIR spectroscopy. Also, polyurethane adhesives were evaluated for their performance and chemical resistance.