Instrument: 7000 Headspace Autosampler
Static Headspace Evaluation of Polymer Emulsions Using the Tekmar 7000HT
The Water-based polymer emulsion samples evaluated by conventional gas chromatography (GC) generally require extensive sample preparation prior to analysis. The samples normally undergo an extraction procedure to solvate lower molecular weight species, and the extraction solvent containing these analytes is injected directly into the GC. Inefficiency of extraction and fouling of the GC system are difficulties that may be encountered. Static headspace analysis offers a very clean technique that can overcome these deficiencies.
Large volumes of water-based samples, however, limit the upper operating temperature of a static headspace analyzer to approximately 15°C below the boiling point of water. As such, many analytes of interest will not be volatilized. But by using a small amount of well-mixed sample, the temperature range for evaluation can be expanded up to 300°C.
The results of two experiments will be presented in this paper. In the first experiment, thin films of a polymer emulsion were examined over a broad temperature range well above the boiling point of water. The samples were analyzed automatically using the Method Optimization Mode feature on the Tekmar 7000HT. In the second experiment, a similar analysis was performed on a commercial paint product that contained the same emulsion polymer in its formulation.
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