| The preservation of museum objects requires careful environmental monitoring, which includes the choice of materials for display cases. Corrosive vapors originating from these materials must be controlled. Thermal Gravimetric Analysis (TGA) coupled with FT-IR detection of vapors, provides a rapid, sensitive, and simple method for analyzing these materials. Essentially, the TGA accelerates outgassing, and the FT-IR spectrometer is an excellent gas analyzer.
Small samples (25-80 mg) of display materials were placed in a TGA coupled to a NicoletTM 6700 FT-IR spectrometer with a TGA-IR interface. The heated transfer line and cell prevent condensation of vapors. OMNICTM Series software was used to collect the FT-IR data.
Eighteen scans at 8 cm-1 resolution were collected, giving a 10 second per spectrum rate of collection, with sufficient resolution for identification. The collection time was coordinated with the TGA run. The maximum temperature of the TGA was set to 200-220°C to enhance the outgassing without causing serious sample degradation.
The TGA-IR Analysis of Museum Materials application note illustrates the results of this analysis and further explains the benefits of TGA-IR. |