Fourier thermal analysis

Alternative approaches consist in heat extraction by means of thermal analysis, thermal volatilisation and (laser) desorption techniques, or pyrolysis. In most cases mass spectrometric detection modes are used. Early MS work has focused on thermal desorption of the additives from the bulk polymer, followed by electron impact ionisation (El) [98,100], Cl [100,107] and field ionisation (FI) [100]. These methods are limited in that the polymer additives must be both stable and volatile at the higher temperatures, which is not always the case since many additives are thermally labile. More recently, soft ionisation methods have been applied to the analysis of additives from bulk polymeric material. These ionisation methods include FAB [100] and LD [97,108], which may provide qualitative information with minimal sample pretreatment. A comparison with FAB [97] has shown that LD Fourier transform ion cyclotron resonance (LD-FTTCR) is superior for polymer additive identification by giving less molecular ion fragmentation. While PyGC-MS is a much-used tool for the analysis of rubber compounds (both for the characterisation of the polymer and additives), as shown in Section 2.2, its usefulness for the in situ in-polymer additive analysis is equally acknowledged. 

Nasraoui, M., Bilal, E. Gibert, R. 1999. Fresh and weathered pyrochlore studies by Fourier transform infrared spectroscopy coupled with thermal analysis. Mineralogical Magazine, 63, 567-578. 

The products obtained are determined by the energy spectrum for the compositions, mainly for the Ca/P mole ratio, and characterized by infrared spectroscopy with the Fourier transformation intra-red spectrophotometer (FTIR) of Type Nicolet 51 OP made by Nicolet Co., thermal analysis on a thermo- gravimetric/differential thermal analyzer (TG/DTA) of Type ZRY-2P, X-ray diffraction (XRD) analysis with the X-ray diffractometer of Type XD-5 made by Shimadzu Co., scanning electron microscopy (SEM), and transmission electron microscopy (TEM) with the transmission electron mirror microscope of Type JEM-100SX type made by JEOL Co. 

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. 

Spectroscopy has become a powerful tool for the determination of polymer structures. The major part of the book is devoted to techniques that are the most frequently used for analysis of rubbery materials, i.e., various methods of nuclear magnetic resonance (NMR) and optical spectroscopy. One chapter is devoted to (multi) hyphenated thermograviometric analysis (TGA) techniques, i.e., TGA combined with Fourier transform infrared spectroscopy (FT-IR), mass spectroscopy, gas chromatography, differential scanning calorimetry and differential thermal analysis. There are already many excellent textbooks on the basic principles of these methods. Therefore, the main objective of the present book is to discuss a wide range of applications of the spectroscopic techniques for the analysis of rubbery materials. The contents of this book are of interest to chemists, physicists, material scientists and technologists who seek a better understanding of rubbery materials. 

Holland, B. J. and Hay, J. N. The kinetics and mechanisms of the thermal degradation of poly(methyl methacrylate) studied by thermal analysis-Fourier transform infrared spectroscopy. Polymer 2001 42 4825. 

A considerable number of different techniques has been employed in the past to characterize the porosity and surface chemistry of porous carbon materials. These include gas adsorption (mostly N2 and CO2) [9-14], immersion calorimetry [9], small-angle X-ray [11,15] and neutron [14] scattering, inverse gas chromatography [12,13], differential thermal analysis [12], Fourier transform infrared [12], Raman [16] and X-ray photoelectron [17] spectroscopies and electron spin resonance [16]. It is worth mentioning that the information about the porous structure of the material provided by this array of techniques is only indirect... 

Mineralogical techniques such as X-ray diffraction, differential thermal analysis, Fourier transform infrared analysis, and Mossbauer spectroscopy may be useful for determining modes of occurrence of major elements in coal, but the ability of these techniques to determine the modes of occurrence of the minor- and trace-elements is quite limited. X-ray absorption-fine structure (XAFS) spectroscopy has been used to determine the modes of occurrence of several important minor and trace elements (e.g., arsenic and... 

Shalliker, R.A. Douglas, G.K. Rintoul, L. Russell, S.C. The analysis of zirconia-silica composites using differential thermal analysis, Fourier transform-Raman spectroscopy and X-ray scattering/scanning electron microscopy. Powder Technol. 1998, 98, 109-112. 

According to the structure and composition of materials and analysis requirements of the researcher, the following analysis techniques can be selected for the characterization of mesoporous materials XRD, TEM, adsorption-desorption (N2 or other gas), solid MAS NMR (29Si, 27Al, 13C, etc.), scanning electron microscopy (SEM), catalysis test, Fourier Transform infra-red (FT-IR), thermal analysis, UV-visible, and chemical analysis. IR, X-ray photoelectron spectroscopy (XPS), X-ray absorption near-edge structure XANES, extended X-ray absorption fine structure EXAFS and other spectral methods are commonly used to analyse metal elements such as Ti in the mesoporous material frameworks. 

Metal oxide and hydroxide systems serve many functions, including roles as pigments, in mineralogy, and also in catalysis. The classic techniques used in such investigations have included diffraction (especially X-ray diffraction XRD), thermal analysis, transmission electron microscopy, Fourier transform infrared (FTIR) spectroscopy and Raman spectroscopy (see also Chapters 2 and 4). Until the introduction of voltammetry in the analysis of immobilized microparticles, electrochemical studies had been confined to solid electrolyte cells (Chapter 12), normally functioning at elevated temperatures. Unfortunately, these studies proved to be inapplicable for analytical characterization, and consequently a series of systematic studies was undertaken using immobilized microparticles of iron oxides and oxide-hydrates (for reviews, see... 

Direct methods of analysis such as ultraviolet (UV) absorption, infrared spectroscopy (IR), fluorescence, phosphorescence [13], X-ray fluorescence [14-16] and thermal analysis [17] have been reported. However, these methods generally lack specificity [18]. In Fourier transform IR (FTIR), overlapping bands of other species may interfere with the absorbance bands of the analyte, and in UV analysis the absorbance bands of different antioxidants can be very similar. UV and FTIR analysis are especially useful techniques when an antioxidant system is already known. X-ray fluorescence and elemental analysis are fast and useful techniques for the determination of antioxidants containing phosphorus or sulfur. The measurement of oxygen consumption... 

A combination of techniques, such as powder X-ray diffraction (XRD) [56, 58], thermogravimetric analysis (TGA) [57], differential thermal analysis (DTA) [57], X-ray photoelectron spectroscopy (XPS) [56, 58], scanning electron microscopy (SEM) [26, 57], Fourier transform infrared (FT-IR) spectroscopy [57, 58] and BET N2 adsorption measurements [67], was used for structural characterization of the enzyme-clay conjugates. 

The spent catalysts were characterized by chemical analysis (carbon content), temperature programmed oxidation coupled to a mass spectrometer (TPO/MS) and thermal analysis (DTA and TG). The samples were also submitted to extraction of soluble coke in a soxhiet apparatus with n-hexane and dichloromethane for 24h, after being treated with fluoridric acid (40%) at room temperature (2h), followed by reflux with hydrocloric acid (36%) for 2h. The extracts were analyzed by gas-chromatography-mass spectrometry (GC/MS), Fourier transformer infrared spectroscopy (FTIR), ultraviolet spectroscopy (UV) and X ray diffraction. The insoluble fraction was analyzed by X ray diffraction and FTIR. 

Pulse thermal analysis (PulseTA ) [1] eliminates, or at least reduces, the difficulties mentioned above. PulseTA is based on the injection of a specific amount of the gases or liquids into the inert carrier gas stream and subsequent monitoring of changes in the mass, enthalpy and gas composition, resulting from the incremental reaction extent. Because a known amount of the selected gas, which can be used for calibration, is injected into the system, the method is also suitable for quantification of the evolved gas by mass spectrometry (MS) or Fourier transform infrared spectroscopy (FTTR). In contrast to conventional TA and all its modifications, the reaction is controlled not only by the temperature, but also by a distinct change in the composition of the reactive atmosphere. 

Analytical services include optical microscopy, scanning electron microscopy, transmission electron microscopy, electron probe microanalysis, scanning auger microanalysis, electron spectroscopy for chemical analysis, x-ray fluorescence, x-ray diffraction, thermal analysis (DSC, DTA, TGA, TMA) and Micro-Fourier transform infrared spectroscopy. 

G.A. Senich, WJ. MacKnight, Fourier transform Infrared thermal analysis of a segmented polyurethane. Macromolecules 13 (1) (1980) 106-110. 

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