An automated analysis system consisting of a dynamic headspace (DHS) system coupled with thermal desorption-Gas Chromatography/ Mass Spectrometry (TD-GC/MS) was used for fully automated microscale chamber material emission analysis of Spray Polyurethane Foam (SPF). Closed-cell and opencell SPF samples were analyzed for emissions of TVOCs and high boiling compounds such as, for example, fl ame retardants and amine catalyst. Foam samples were analyzed qualitatively, and 15 hour emission tests subsequently carried out to investigate off-gassing mechanisms of the foams. The effect of sample temperature was examined using an automated sequence in which the sample temperature was changed at defi ned times to simulate the heating of foam insulation in attics or roofs. The experiments provided unattended operation with precise control and documentation of the principal variables in micro-scale chamber experiments: Time, gas flow, and temperature. Samples were subsequently analyzed using the VDA 278 method with direct thermal desorption at 90°C to determine VOC emissions. Good correlation was obtained between the two methods from a qualitative point of view. Semi-quantitative results were obtained using toluene equivalents.

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Dynamic Headspace Large (DHSLarge)

The DHS can be extended with the DHSLarge module to perform analysis of large or inhomogeneous bulk samples. For example, consumer products, packaging or flooring material can be placed directly in sample containers up to 1L in volume. Sample holders are available for flooring material, eliminating interfering emissions from the edges of the cut sample. Purge periods can be introduced to simulate air exchange conditions in environmental chambers. A series of analyses can be performed on a sample to determine emission behavior over time. DHS operation or DHSLarge operation is selected by mouse-click.

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