Moisture management for a successful analysis of polymers with chemical sensor systems

This study focuses on the moisture impact on headspace analysis and its implications to the use of chemical sensor systems with a special focus on polymer applications. The results showed clearly that different moisture contents of the polymer samples influence the headspace composition of the samples and change the sensor discrimination. However, the influence of the headspace composition is not only a sensor problem since it influences also the results of gas chromatographic headspace measurements as well as it could influence the human sensory perception. For the quality assurance with a QMB-based sensor system, a pragmatic solution was presented. The polymers, HDPE and PET, could be analyzed directly in the presence of unknown moisture contents after a calibration that took care of the water-influenced vector. The polymer, PA, required a sample treatment prior to analysis.