Thermogravimetry - Gas Chromatography - Mass Spectrometry

Volatile additives for vulcanised or unvulcanised rubbers can be accurately identified by TG or by controlled heating of a test sample in a sealed vial equipped with an overhead collecting headspace, transferring the heated volatile substances to a chromatographic column and analysing the separated volatile components emerging from the chromatograph column by various selective analytical detectors. Several illustrative examples were mentioned before. 

8 Thermal Desorption - Gas Chromatography - Fourier Transform Infrared Spectroscopy/Mass Spectrometry 

The coupling of thermal desorption and identification techniques constitutes a powerful means for the detailed characterisation of outgassing processes with many potential applications in the field of rubbers. 

Jansen and co-workers [86] have evaluated temperature-controlled outgassing processes of plastics and rubbers using both off-line and on-line TD-GC-FTIR-MS. Decomposition of polyesterurethanes by means of TG-Tenax off-line sampling followed by TD-GC-FTIR-MS revealed C02, H20, tetrahydrofurane, cyclopentanone, dicarbonic acid, aliphatic diols and esters [86]. The same authors have also described the detection of polychlorinated biphenyls (PCB) in 2,4-dichlorobenzoylperoxide cured silicone rubbers after outgassing products of a rubber silicone part obtained after desorption for 10 minutes at 200 °C in the thermal desorption cold-trap and subsequent analysis by means of TD-GC-MS. Using a mass range of 290-294 Da the MS can be used as a selective detector for these substances. 

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Chung, H.L. and J.C. Aldridge Thermal study of licorice ACD, 1992, No. 259, September 15, see www.ijrt-docs.com 508392999 -3005 Thermal study of licorice by online thermogravimetry/gas chromatography/mass spectrometry 53rd Tobacco Science Research Conference, Program Booklet and Abstracts, Vol. 53, Paper No. 7, 1999, p. 23. 

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