Reagent-loaded and unloaded polyurethane foam as preconcentration matrix in neutron activation analysis

Loaded and unloaded polyurethane foams were examined as a preconcentration matrix in combination with neutron activation analysis. The structure of the foamed polymer is not damaged by short irradiation periods. However the foam skeleton degraded after irradiations for one hour or longer in a neutron flux of 3x1013nxcm-2xs-1. The presence of tin as a major impurity in the polyether-type foam has been detected. This may affect the sensitivity of determination of the relatively short lived isotopes of the elements collected on the foam. On the other hand the polyester-type foam was found to cortain only very iow amounts of tin. Antimony, indium, gold and mercury collected on the foams were determined with reasonable accuracy. (author)