Thermogravimetry-differential thermal analysis-mass

Thermogravimetry - Differential Thermal Analysis - Mass Spectrometry... 

Z. Zheng and Q. Gao, Decomprosition of NH3BH3 at sub-ambient pressures A combined thermogravimetry-differential thermal analysis-mass sp>ectrometry study, /. Power Sources 196, 2011,1615-1618. 

The synthesis of the complex is followed by the most important step of characterization of the complex. The composition and the structural features of both the ligand and complex have to be established before embarking on further studies. There exist many methods by which the composition and structural features of the complexes are studied. Some of the methods are (i) elemental analysis, (ii) X-ray crystallography, (iii) UV-Vis absorption spectra, (iv) infrared spectroscopy, (v) Raman spectroscopy, (vi) thermal methods of analysis such as thermogravimetry, differential thermal analysis, (vii) nuclear magnetic resonance spectroscopy (proton, multinuclear), (viii) electrospray mass spectrometry. Depending upon the complexity of the system, some or all the methods are used in the studies of complexes. 

A few years later, Zhao et al. also studied the thermal stability and chemical structure of SEI formed on a natural graphite electrode in LiPFg EC/DMC electrolyte by thermogravimetry-differential thermal analysis combined with mass... 

The techniques referred to above (Sects. 1—3) may be operated for a sample heated in a constant temperature environment or under conditions of programmed temperature change. Very similar equipment can often be used differences normally reside in the temperature control of the reactant cell. Non-isothermal measurements of mass loss are termed thermogravimetry (TG), absorption or evolution of heat is differential scanning calorimetry (DSC), and measurement of the temperature difference between the sample and an inert reference substance is termed differential thermal analysis (DTA). These techniques can be used singly [33,76,174] or in combination and may include provision for EGA. Applications of non-isothermal measurements have ranged from the rapid qualitative estimation of reaction temperature to the quantitative determination of kinetic parameters [175—177]. The evaluation of kinetic parameters from non-isothermal data is dealt with in detail in Chap. 3.6. 

Leinweber P, Schulten HR. Differential thermal analysis, thermogravimetry and in-source pyrolysis-mass spectrometry studies on the formation of soil organic matter. Thermochim. Acta 1992 200 151-167. 

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. 

Mara. Kamei and Osada [109 described a detailed study of the thermal decomposition of TNT. They examined the decomposition by differential thermal analysis, thermogravimetry, infra-red spectroscopy. HSR and mass spectrometry. One of their most important findings was that TNT produced free radicals already in the vicinity of the melting point, that is SO C. The substances which promote the decomposition of TNT are free radicals which are stable at room temperature. They are insoluble in benzene or chloroform and are partly oxidized polymeric substances. 

Applying conventional (thermogravimetry TG Differential thermal analysis DTA evolved gas detection EGD) and combined (thermogravimetry-mass spectrometry TG-MS) techniques, the pCD inclusion complexes with thymol and Lippia sidoides Cham EO (LsCEO) extract produced by kneading method were characterized. Its formations were detected through released gas... 

Borazine, (-BH-NH-)3, is formed by heating solutions of H3N-BH3 in ether or acetonitrile, as shown by B NMR [1], and in the thermal dissociation of H3N-BH3, as shown by thermogravimetry (TG) and differential thermal analysis (DTA) [2]. The thermal decomposition mass spectra of (-BH2-NH2-)n under El conditions contain the ions [B3N3H5] as the base peak and [B3N3H6] with 39% relative intensity [3]. 

Thermoanalytical methods comprise calorimetry (Differential Scanning Calorimetry, DSC) and thermogravimetry (TG) [3]. Mostly, the temperature of the sample is increased linearly and peaks of the sample temperature in comparison to a reference sample are recorded (Differential Thermal Analysis, DTA). In thermogravimetry the mass loss is observed. In this way the content of adsorbed liquids can be determined and the desorption kinetics can be observed. For special tasks also a quasi-isothermal treatment may be applied [4]. The most important standards on such methods are summarized in Table 2. 

Although water is known as a natural plasticizer for many polar polymers such as nylon, polyester resins, and cellulosic polymers, similar behavior for polyacrylamide and poly(acrylamide-co-acrylic acid) has not been investigated. In this study, the effect of water content (and/or thermal history) on the Tg s of acrylamide-based pol3 TOers was studied by Differential Scanning Calorimetry (DSC), Thermogravimetry (TG), Thermomechanical Analysis (TMA), and Simultaneous Thermogravimetry - Mass Spectrometry (TG/MS). 

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