Structure elucidation of aminophenols-iodine redox products by emanation thermal analysis

The structures of polymers I and II and the dimer III that formed during the oxidation of o-, p- and m-aminophenol respectively with iodine have been studied previously by TGA, DTA, and elemental and spectral analyses. In the present work these structures were confirmed by emanation thermal analysis (ETA) of the compounds. The possible structural changes of these polymeric and dimeric forms were followed at different temperatures by measurement of emanation power under various conditions. The schemes representing the possible chemical and physical changes were suggested during gradual heating, isothermal heating and gradual cooling at different stages. The results were in good agreement with those of normal TGA and DTA. Detailed changes were detected and identified by the non-traditional technique of ETA which could not be identified by conventional methods of analysis. © 1991.