Leaching of radio-oxidized poly(ester urethane): Water-soluble molecules characterization

Abstract : In the context of the geological nuclear waste storage, water-soluble products of an industrial poly(ester urethane) are investigated. This polymer was radio-oxidized up to 10 MGy with gamma rays under air at room temperature. The unirradiated and irradiated materials were hydrolyzed for 28 days at 60 C in pure water (MilliQ water). The solutions were characterized using different analytical tools (total organic carbon analyzer, ionic chromatography, gas chromatography coupled with mass spectrometry and tandem mass spectrometry). From 11 to 30 per cent of the water-soluble molecules present in the solutions have been quantified. Most of molecules identified are esters, alcohols, carboxylic acids, diols and ketones. Mechanisms were deduced from the detected molecules. It was observed that the irradiated material was about 70 times more sensitive to hydrolysis than the unirradiated one.