The polymer was synthesized by the polymerization of 4, 4′-((4-iodophenoxy) methyl)-2, 2′-bipyridine (M-1) with 4, 7-diethynylbenzo [2, 1, 3]-thiadiazole (M-2) via Pd-catalyzed Sonogashira reaction. The fluorescence responses of the polymer towards various transition metal ions were investigated by fluorescence spectra and UV–Vis spectra. The polymer shows green fluorescence under ultraviolet lamp, which can be quenched by Cu2+ ...