Thermogravimetric analysis Mass spectroscopy

Recently, MS combinations have been available including the thermogravimetric analysis mass spectroscopy (TG-MS) combination developed by Carraher that allows the continuous characterization of evolved materials as a polymer undergoes controlled thermal degradation. 

Koh et al. also made a comparative study of the mechanism of precursor decomposition of PbSe NRs synthesised from TDPSe and spherical PbSe NCs prepared from TOPSe precursor. They studied the role of temperature, free phosphine and amine on the decomposition of the selenium precursors by P NMR, thermogravimetric analysis-mass spectroscopy (TGA-MS) and UV-Vis spectroscopy. The P H NMR spectra indicated selenium precursor decomposition for the TOPSe-based synthesis at 50-60 °C, whereas for TDPSe-based synthesis high selenium precursor decomposition was found only at 150-160 °C. This was further confirmed by absorption spectroscopy, which showed a peak for the formation of PbSe from TOPSe at low temperatures with no such feature observed with the TDPSe-based synthesis due to steric hindrance in the precursor which prevented its decomposition at low temperatures. 

Perng [54] used stepwise and thermogravimetric analysis/mass spectroscopy techniques at temperatures between 650 and 1050 °C to study the mechanism and kinetic model for thermal decomposition behaviour of PPS. 

Thermogravimetric analysis Differential thermal analysis Differential scanning calorimetry Thermal volatiUszation analysis Evolved gas analysis Mass spectroscopy methods Matrix-assisted laser desorption/ionization Imaging chemiluminescence... 

In this study, we extend the range of inorganic materials produced from polymeric precursors to include copper composites. Soluble complexes between poly(2-vinylpyridine) (P2VPy) and cupric chloride were prepared in a mixed solvent of 95% methanol 5% water. Pyrolysis of the isolated complexes results in the formation of carbonaceous composites of copper. The decomposition mechanism of the complexes was studied by optical, infrared, x-ray photoelectron and pyrolysis mass spectroscopy as well as thermogravimetric analysis and magnetic susceptibility measurements. 

High performance liquid chromatography (HPLC) and with mass spectrometry (LC-MS) Plasma emission spectroscopy (PES) Scanning electron microscopy (SEM) with elemental X-ray analysis Thermogravimetric analysis (TGA)... 

The thermal characterisation of elastomers has recently been reviewed by Sircar [28] from which it appears that DSC followed by TG/DTG are the most popular thermal analysis techniques for elastomer applications. The TG/differential thermal gravimetry (DTG) method remains the method of choice for compositional analysis of uncured and cured elastomer compounds. Sircar s comprehensive review [28] was based on single thermal methods (TG, DSC, differential thermal analysis (DTA), thermomechanical analysis (TMA), DMA) and excluded combined (TG-DSC, TG-DTA) and simultaneous (TG-fourier transform infrared (TG-FTIR), TG-mass spectroscopy (TG-MS)) techniques. In this chapter the emphasis is on those multiple and hyphenated thermogravimetric analysis techniques which have had an impact on the characterisation of elastomers. The review is based mainly on Chemical Abstracts records corresponding to the keywords elastomers, thermogravimetry, differential scanning calorimetry, differential thermal analysis, infrared and mass spectrometry over the period 1979-1999. Table 1.1 contains the references to the various combined techniques. 

For our investigation we used several analytical methods FT-IR spectroscopy, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and mass-spectroscopy. 

Infrared spectroscopy has also been combined with other established analytical techniques, e.g. thermogravimetric analysis (TGA). The latter is a technique which involves measuring the change of the mass of a sample when it is heated. While TGA can provide quantitative information about a decomposition process, it is unable to identify the decomposition products. However, TGA and infrared spectroscopy have been combined to provide a complete qualitative and quantitative characterisation of various thermal decomposition processes. 

Tremendous advances have been made in the past few decades in both the range and sensitivity of the analytical methods now available. For the purpose of solubility measurement, solution compositions can be measured by any eonvenient analytical technique, among which may be listed liquid chromatography (HPLQ, spectroscopy (UV, IR, NMR and mass), differential scanning calorimetry (DSC), differential thermal analysis (DTA), thermogravimetric analysis (TGA), refractometry, polarimetry, and most recently capillary electrophoresis (Altria, 2000). 

Thermogravimetric analyzers may be connected to a variety of chemical analyzers to determine the exact composition ofthe outgassed materials as they are evolved. Among chemical analysis methods are gas chromatography, infrared spectroscopy, and mass spectroscopy for example, a TGA apparatus may be coupled with a Fourier Transform Infrared (FTIR) spectrophotometer to measure the thermal oxidative stabilities of several fluorinated polyimides. 

Instrumentation used for polymer oxidative stability (Chapter 11) includes, thermogravimetric analysis, differential scanning calorimetry, evolved gas analysis, infrared spectroscopy and ESR spectroscopy, matrix assisted laser desorption/ionisation mass spectrometry and imaging chemiluminescence is included. 

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