Abstarct: 4-iodobenzoic acid was refluxed with thionyl chloride the residue was filtered off, dried to give 4-iodobenzoylchloride. The resulted compound reacted with sodium azide dissolved in acetone and water, the solid was filterd off, dried to give white powder. 4-iodobenzoyl azide was refluxed in tolouen then reacted with Ethylhydrazincarboxilate the powder of 1-ethoxy carbonyl-4-(4-iodophenyl)semicarbazide was filtered off. 1-Ethoxycarbonyl-4-(4-iodophenyl)semicarbazide and a water solution of potassium hydroxide were added for neutralization, then 4-(4-iodophenyl)-1,2,4-triazolidine-3,5-dione precipitated as powder The structure of this compound was confirmed using infrared spectroscopy, thermal analysis and CHN analysis. 4-iodophenyl urazole was reacted with equal mole of hexamethylene diisocyanate (HMDI), diphenylmethan-4,`4-diisocyanate (DPMDI) and tolylen diisocyanate (TDI) in dimethylformamide (DMF) to produce novel related polymers. The structure of these polymers were confirmed using infrared spectroscopy, viscometery, thermal analysis (TGA-DTG) and CHN analysis. 4-iodophenyl urazole was reacted with 2 moles of hexamethylene diisocyanate (HMDI), diphenylmethan-4,`4-diisocyanate (DPMDI) and tolylen diisocyanate (TDI) and equal mole of phenyl urazole in dimethylformamide (DMF) to produce novel related copolymers. The structure of these copolymers were confirmed using infrared spectroscopy, viscometery, thermal analysis (TGA-DTG) and CHN analysis.