Thermally stable zinc(II) Schiff base polymers (decomposition temperature up to 461 °C; M_n = 13580 to 20440) formed by self-assembly reactions of zinc(II) salts and salicylaldimine monomers exhibit blue to yellow PL with quantum yields up to 0.34 in DMF; PLEDs employing these polymers as emitters give green or orange EL with turn-on voltage at 5 and 6 V and maximum efficiency of 2.0 and 2.6 cd A⁻¹ respectively.