Dacron is the iconic commercial and brand name for polyethylene terephthalate (PET), a synthetic thermoplastic polymer belonging to the polyester chemical family. Its chemical structure consists of repeating linear ester monomer units formed through the condensation polymerization reaction between ethylene glycol and terephthalic acid. This polymeric arrangement yields a semi-crystalline macromolecular structure characterized by strong intermolecular hydrogen bonds and rigid benzene rings within the backbone chain. This ordered configuration grants the material exceptional tensile strength, high resistance to stretching and chemical degradation, and superior dimensional stability.