The hybridization of poly(ethylene terephthalate) (PET) with montmorillonite (Mont) was investigated by using hydroxyethyl isonicotinamide (HENA) as an ionic anchor monomer capable of being adsorbed onto clay surfaces by a pyridinyl group (-C5H5N). The hybrid films of HENA/Mont with bis(hydroxyethyl) terephthalate (BHET) exhibited favorable characteristics of being optically clear and transparent.