Price, Duncan M.; Hourston, Douglas J.; Dumont, Fabrice; Thermogravimetry of Polymers. Encyclopedia of Analytical Chemistry Meyers, R. A. (Ed.) John Wiley & Sons Ltd., Chichester (2000) pp. 8094-8105
Thermogravimetry (TG) is the study of the relationship between a sample's mass and its temperature. TG can study any physical (such as evaporation) or chemical process (such as thermal degradation) that causes a material to lose volatile gases. Polymers have different thermal stabilities and thus the qualitative "fingerprint" afforded by TG in terms of temperature range, extent and kinetics of decomposition provides a rapid means to distinguish one polymer from another using only milligram quantities of material. Experiments are most commonly carried out under conditions where the temperature is increased in a linear fashion with time or the sample is held isothermally at an elevated temperature - although more sophisticated temperature profiles are occasionally employed for compositional and kinetic analysis. Processes which do not result in a change in sample mass are not detected by TG. Therefore simultaneous measurements by differential scanning calorimetry are useful. Volatile decomposition products may be detected and identified (e.g. by infrared spectrometry or mass spectrometry in order to elucidate the mechanism of mass changes. TG is used for quantitative compositional analysis of polymers, lifetime prediction and kinetic studies making the technique invaluable in all stages of polymer development, fabrication and component testing.
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