Application note Nitrogen analysis in various polymers with the rapid MICRO N cube The rapid MICRO N cube measures low level nitrogen concentrations with a detection limit of 10mg/kg using the Dumas method. After reduction of the oxides of nitrogen the resulting N2 is measured using a thermal conductivity detector. Until now such low level concentrations were measured via oxidation to NO followed by chemiluminescence detection. This method is, however, matrix dependent and needs a matrix dependent calibration. Solid polymer samples have been weighed into tin boats. After closing the sample they have been pressed with a manual pressing tool in order to remove remaining air from the sample. The sample weight of the polymer samples was about 20 mg. instrument: rapid MICRO N cube sample: 20 mg polypropylene granulate polyethylene granulate HDPE granulate polyethylene foil The results show that the rapid MICRO N cube is very well suitable for the analysis of nitrogen concentrations in polymer samples. Nitrogen concentrations down to 56 mg/kg have been analyzed with a high precision. The rapid MICRO N cube offers the matrix independent Dumas method in combination with high sensitivity, ideal for applications in the polymer industry. Elementar Analysensysteme GmbH Donaustraße 7 63452 Hanau, Germany phone: +49 6181 9100-0 email: [email protected] web: www.elementar.de